May I suggest Tracker Control, allows per-app network access and even restricts certain tracking requests. Only downside is it takes the VPN slot. Very much worth it though I believe

Depends on when the app pulls from OSM. Organic Maps and OSMAnd are monthlyz, if you have OSMAnd plus or are a contributor to OSM it’s hourly I think

OsmAnd was specifically designed for offline use, downloads the maps and runs the routing all offline. Can do both online as well but by default after download it’s all offline

I has problems with that too but I reckon it was fixed a few weeks ago, rerouting is basically instant from what I can tell, but maybe I configured it to be a bit better in the settings and forgot… Also try organic maps of you want another alternative

Used to use Niagara launcher, but moved to kvaesitso since it’s FOSS. Both are very very good.