I am wondering if I can make a chat system where players can press a button that has a smiley emoji on it, and the chat says like, “flyingteleportingc: ” or not?

when green flag clicked
help me with Scratch pls

yep! it's allowed as long as its limited to just pressing buttons and not custom inputs such as typing out your text since im pretty sure custom chat is not allowed. same goes with selecting built in words like “hi” and “help me”

Yes, emoji-only chats are allowed according to Scratch's rules for cloud chats:

What about projects that allow people to share emojis with each other, or that use a few pre-made sentences?

These are generally fine as long as they can't be used to share content that the people viewing the project can create themselves.

ninja'd

As long as you can’t actually type something (so presets only), yes, stuff like emojis, it’s allowed!