The FUTO keyboard is pretty good. All offline, customizable design, good speech recognition, tolerable swipe typing. It's published under a distinct opensource-ish license if you care about that. It's technically a paid app but with an indefinite trial period and and a license checking scheme based on human trust (click the 'yes I bought it' button and it accepts). Worth $5 imo, I bought additional copies for friends and family too.

https://keyboard.futo.org/

https://github.com/futo-org/android-keyboard