If you keep your username and avatar, people will still recognize you, I do that regularly every few months, so on the "persona" aspect people should be fine.
About the "archive" aspect, the content is still there, not sure how often people have to go back to their past posting history. Saving past important comments and posts from an old account is still an option.
Thank you for offering, some communities might ask you for help!
Personally I tend to try to find active members who are known to be positive in the community before reaching out to them and offering them a mod position. It's easier for them to mod if they're already invested in the community.
Also, the animation link seems broken, here's another one: https://lemm.ee/post/65945910?scrollToComments=true