Comment by NoDodgeQuestion

Here's a tip if you use google maps: if you want to get from A to B but can walk a bit, just pick a point C between them then look up directions to and from point C separately. Works great

It's not exactly what you asked for, but the public transit and multimodal focused apps are generally much better at this stuff. I like CityMapper and Transit.

Neither is good for turn-by-turn directions, but both are good for "what are all the different ways to get there"

The public transport app in my city almost does this well, it even affords cycling. But it isn’t quite as nuanced as one would like.

I wish I could add certain streets and routes to some sort of block list.

There are certain roads I would be willing to spend an extra 10-30 minutes driving to avoid. (And certainly would not get on them on a bike!)

Not to mention “public transit but with a waypoint” which is too advanced for all mobile apps