Tes Vampires are very fascinating they tend to be unique for vampires in different ways. Vampires have been very interestingly portrayed since Arena and Daggerfall.
Most of all is how they come to be and how they invert many undead tropes. Tes vampires are not reanimated corpses that is my opinion its how I see well them. Most of the stuff I'm writing is theories /speculation on how it works plus circumstantial evidence that has been seen throughout the series that seems to support it. So that is a disclaimer. (Daggerfall has to be considered either retconned lore or a lot of it reworked))
Spoilers to cut down on thread size
However what is portrayed time and again and also in Eso. To become a vampire requires you to be infected and then you transition into one. But the requirement is to survive a vampire attack.
Once said and done once the process is complete that person becomes a vampire. In most vampire folk lore or fiction a vampire must die to transition into a vampire. Tes does the opposite and requires the person to be alive for the transformation to take hold (Vestige was unique in they had to be drained a lot of the immortal blood or life force and then given the blood of the first vampire in order to become one. As they are immortal not mortal)) Because of this vampires do seem to have enough life in them even though reality might think they are cut off from the cycle of life and most importantly decay but they still have that life in them as they come from life explaining the reason why they have heartbeats and also explaining how they can drown.
However vampires are shown to be able to survive when being trapped in coffins and even going so far as appearing dead.
One npc mentions vampires still they still have heartbeats and obviously have to breath. However there is also a counter example as well. Put into spoilers as not to clutter the post.
https://en.uesp.net/wiki/Online:Melina_Cassel
144 Melina Cassel Be still my beating heart! Lyam arrived at our door at he looked simply smashing! (And, yes, contrary to popular belief, our hearts beat quite well, thank you.) How handsome the scion of the Fontbonne family looked in his finery! And, I'm pleased to say, he seemed as impressed by my appearance as I was by his. He took my hand and we were off.
There is a counter example that shows that this might not be the case for all vampires and some might not have heartbeats.
https://en.uesp.net/wiki/Lore:Ongoing_Journal_of_Galur_Rithari
Days passed in the depths of Bal Ur and in my dying delirium I began to dream. At first it was divine. I felt the warm coastal breeze of Vivec City unblemished by the shadow of Baar Dau. Love and kindness surrounded me as I saw the radiant visage of Lord Vivec approaching. I felt forgiveness, and peace, but as Vivec grew closer he twisted into something truly putrid, something vile beyond words. I soon recognized the sight of Molag Bal's pitiless grin before the Daedric Prince's fangs plunged into my heart. In my fright, I woke, shivering and colder than death, but it was the absence of thunder in my chest that revealed my affliction. My disease.
Tes vampires may not be reanimated corpses however they do seem be in partial state of
https://en.wikipedia.org/wiki/Suspended_animation
Suspended animation is the temporary (short- or long-term) slowing or stopping of biological function so that physiological capabilities are preserved. It may be either hypometabolic or ametabolic in nature. It may be induced by either endogenous, natural or artificial biological, chemical or physical means. In its natural form it may be spontaneously reversible as in the case of species demonstrating hypometabolic states of hibernation or require technologically mediated revival when applied with therapeutic intent in the medical setting as in the case of deep hypothermic circulatory arrest (DHCA)
So in a way they live in a state of suspended animation. However its not a full on state of suspended animation. When they are awake that is.
This is shown in several ways. Spoiler ed to keep thread size down.
They don't age.
They don't decay.
They can forgo eating and drinking normal people food if they wish.
However they
They still have to breath.
They may or may not have a heartbeat but could depend on how well fed. Heartbeat might be slower at higher stages of hunger or even strain of the condition.
When they sleep its shown they can become more death like and it appears other biological processes are frozen much like a corpse. However they are just in a more complete state of suspended animation. This is shown in Serana and Rona Hassildor, Vicente Valtieri I believe also shows this in oblivion. Vampires you see sleeping in coffins in Elder Scrolls Dawnguard. Seem to be in a similar death like suspended animation.
However like many different kinds of vampire folk lore. Tes Vampires are shown to be able to take up a state of vampiric hibernation.
In the case of two vampires from Skyrim this was basically forced upon them or they had to take up a vampiric hibernation to survive.
https://en.uesp.net/wiki/Skyrim:Vighar
He was trapped in a coffin and basically buried and imprisoned in a coffin much like Barnabas Collin. Unlike Baranabas the undead portrayed. Tes Vampires still need air, and being in a panicked state. Depending on how much oxygen the vampire uses up that vampire would end up suffocating in one hour or even two hours possibly at the max. Because clearly they are able to drown and if they are able to drown they are able to suffocate. Thus a big nord like Lyris could pretty much suffocate them to death.
Serana also seemed to be able to survive and avoid suffocation do to also being in a hibernation type state. Almost forgot to mention her.
However it seems going into hibernation would allow a vampire to survive for many centuries just like other vampire fiction while also being almost dormiate biologically. So its not like they wake up and then scratch at the walls of their coffins every day and going very thirsty as a result. This also explains how both Serana and Vighar were able to survive being entombed. Anyways to the point.
I would like a few vampiric sleeping emotes that allow us to appear dead and in suspended animation like not appearing to breath.
One version would look like this.

They have another stance that can also be added in for a vampiric sleep emote. Or sleep alteration they have this already in the game.
Star Trek Online had another emote that could be used as another inspiration for a vampire sleep emote. So there can be several they could add in here.
Not my screenshot just the only pic I can find on google showing it off.

That would also make a great death like sleep emote.
This is a screen shot of my one character I took this last night.

If only my fps would be 21 throughout the entire game play because it tends to below ten most of the time but because I was in a small inn room it tends to be higher in small interiors.
She looks nice but she still breaths while sleeping. I'd like emotes that take out the breathing look and give vampires a more suspended animation like type of sleep. So who else thinks they should add in some unique vampire sleeping poses? Its something I've been wanting to see for a while. Given vampires are getting love this year I'm hoping they give them love when it comes to unique sleeping emotes. Please do this for us Zenimax *puppy eyes*