Chat does not load for a long time for both players. You chat to the other person the other person can not see your chat and you can not name items in the anvil or use signs with visible words. Only the person creating the sign can see the words. Anvils will not let you rename anything.

steps to reproduce:
1. have 2 people join realm both chat and put sign down to try to communicate. you won't be able to see each others chats nor words on signs.
2.wait about an hour or until chat spam loads everything that has been sent from every player while it wasn't working. Sometimes loads player chat after player has already quit realm.

Workarounds include: /say command, but I have to give op to everyone on the realm to chat which presents a security issues! Otherwise have to use discord to communicate.