Comment by GaronG

I've used a few and got so invested that I built my own. If I had to suggest some, they are also all Open Source:

Handy - It's great, supports Mac, Win and Linux. It's very focused on dictation, but it doesn't go too far outside of that. It's also completely free https://handy.computer/

VoiceInk - Mac only, and pretty good if you're on a Mac. It starts at $25 for one device. https://tryvoiceink.com/

Glimpse - the one I built. Mac and Windows, free local dictation. A lifetime license covers other paid features, w/ a 2 week free trial. https://tryglimpse.cc