FUTO and GBoard has the feature you're describing and I use it all the time. Pretty much anything you miss from Pixel UI can be attained by simply installing Google's app from the playstore.

> I've found graphene's keyboard far more error-prone than the stock android keyboard, but I also don't care to learn swipe to type.

Graphene's keyboard is the stock AOSP keyboard. Most Android systems ship with their own one instead of it, but that's the one that is built into the system by default.