Hi thank you for your post here on the Zoom Community! This article talks about what is supported with in-meeting chat, in the section about "How to chat in Zoom meetings on desktop" it shows what is supported, including emojis and file sharing (if file sharing is allowed by the host of the meeting)
https://support.zoom.us/hc/en-us/articles/203650445-Chatting-in-a-Zoom-meeting
It is possible to use GIFs in Zoom's chat client, where you are chatting with someone outside of a meeting, but GIFs are not supported with in-meeting chat today. It's on the roadmap though!
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