The Holiday Events In-game achievements that require a collectible should activate on all characters. I'm not talking about title sharing, I'm talking about specific in-game achievements that are for the holiday events. Let me explain. There are a few consume/collect x amount of items to make a memento or skin.
Jester's Festival:
5 Noise Maker Parts to get the Festive Noise Maker Memento
5 Joke Popper Parts to get the Jester's Festival Joke Popper Memento
New Life Festival:
12 New Life Charity Writs to get the Crystalfrost Skin
Witches Festival:
10 Skeletal Marionette Parts to get Skeletal Marionette Memento
These specific tasks reward you with the memento or skin for all your characters account wide. However, the in-game achievement is only accomplished on the character who combined them, even though all your characters get to use it. This makes collecting these very difficult for all your alts. If my alts can use the skin/memento it should fill in that in-game achievement and count for collecting it.
The game already does this for other categories like housing. If I build and place 50 Dining room furnishings in my house and I then bring an alt there it automatically unlocks this in-game achievement for them, even though they did not build or place it there or even have the skill level to make it. Why then can we not use the memento that our main has collected x amount of and have the game recognize that our account knows that memento or skin?
With the implementation of the Grab Bags and the expanding loot pool for every event (both things I like), I think it would really make sense, especially for the grab bags to not have so many things we would need for every alt,. Right now the Skeletal Marionette parts are a problem for collecting the Hollowjack motif pages on an alt character, because the chances of getting the motif page are diluted with the skeletal marionette parts.
This is especially frustrating when all our characters already know that memento/skin and can use it. Collecting and combining them again on an alt gives us nothing ( no rune box to sell) only fills in the in-game achievement on that character for doing it again. I'm only talking about these specific ones not all the in-game event achievements. I know I like to do the event stuff on my alts and earn titles for them too.
I just think that if our alt characters can use these items that they should be recognized account wide and fill in the in-game achievements. So, for example, we don't actually have to collect an additional 170 (18 characters) Skeletal Marionette parts for something we could use after collecting the first 10.