they always work for me! maybe you have them disabled here?
https://www.pokecommunity.com/settings/general 👍
If not which emojis are you trying to post? not all of the existing web emojis are compatible with this forum software, so they may not all show D:
edit: weird, when I first sent this message the thumbs up showed as question marks. I edited it and shows fine though. I can bring it up, but it's more likely to be a weird bug with our outdated forum software, which we plan to replace soon!