A first idea would be to have 3 categories of emojis. positive reactions (thumbsup, smiley, rocket, …), neutral ones (hat, …) and negative ones (vomiting, …). Together with a proper downvote symbol, this could map onto the old categories.
But that’d have to be transparent and intuitive. many users don’t want to learn about specifics. and what exactly votes and what’s decoration. It has to be obvious and work without learning things.