Also seconding a feature for emoji reaction management in chat. We probably can’t turn on chat for the whole forum until there’s a way to restrict emoji reaction in some way.
We have a community with a younger audience and certain emojis are already filtered in our forum (through Watched Words) and app community.
My personal preference was initially for a block list, but from feedback from another moderator on our forum, I guess an allow list would be preferable (like with the Reactions plugin).
There are a whole range of emojis that could be used for negative connotations and it would take really long to go banning them one by one
(e.g. here is a handful of the facial emojis 
)