I feel so sorry for recommending a closed source app in this community, but Genius Scan from Grizzly Labs is the only non-oss app I still use. I think I paid around €30 for the enterprise version so it doesn't bother me with cloud nonsense.
It's all local only (if you want) and the scanning quality is the best I've found. (I used OpenNoteScanner for a few months, sadly it's not even close both in terms of quality and convenience)
I figured I'll mention it as an alternative to MS Lens app that likely sucks in every bit of information it can get its hands on.