I took screenshots because I also found it strange and contradicting to what I know, so here are two quotes from Eng version under the cut: He states directly that they don't 'partake' in drinking wine altogether.. for some reason.Unfortunately, Fennorian's new dialogue isn't on UESP yet, so I don't know what he's saying in the English version.
In case ZOS or anyone else would need references as to why it's a contradiction\weird statement, I've found the source of 'ESO vampires can and will drink wine', screenshots under the cut (taken from YT walkthrough of user
Words By Parker, I've finished the quest too long ago). The dialogue happens during a celebration of sorts, for the context of why Gwendis would even drink it. The dialogue heavily, if not outright straightforward, implies that she had too much wine, and 'won't remember' anything in the morning because of it. Gwendis and Fennorian know each other.
upd: The quest where this happens is ''Dream-Walk Into Darkness'' in Rivenspire.
TX12001rwb17_ESO wrote: »The problem is that Gwendis getting drunk is a plothole, lorewise Vampires are not effected by poison which would include the effects of Alcohol, physically they would be unable to get drunk.