It would be ideal to be able to see emoji on a per contact basis. Some of my contacts use iOS, some use Android Oreo, and some use older builds of Android (Blob). I'd like to be able to see the actual Emoji they will be receiving depending on which contact I'm sending to so that I don't have to dig into the settings menu to change the Emoji theme every time I want to see what an iOS user will see.

This would need to be a setting I define because there's no way to know what the contacts are using Emoji-wise on their devices. it could be a per conversation customization.

This could carry over to MMS as far as showing what someone actually sent by continuing to associate specific contacts with specific emoji sets. (I'm okay if it uses more memory to do this 😉)

The MMS thread would have it's own Emoji setting but that wouldn't be associated with any particular contact. It would mainly be used to check what you're sending against what some of the conversation members are using.