Repair/replace moisture-damaged plank wall/framework/floor structure?

[Kalcain]

As a newcomer to the forum, I'm going in strong:
I have a big project ahead of me. Built in 1947. Masonry basement, one residential floor, and a crawl space attic.
One of the long sides facing south (and to some extent also the west-facing short side) has been weathered over the years. In combination with poor maintenance, hasty decisions, and general neglect, it has created a considerable moisture and rot damage in the sill against the masonry foundation and in the standing, tongue-and-groove plank wall (50x120 plank type). Even the joists are severely damaged in some places on the outer edge. The house has been vacant and unheated for an extended period, and the first thing I found in the wall when I opened up the corner was a black ant colony... Oh the joy!

My big question now is: Is it possible to repair and replace the bad parts without removing the entire wall and without having to support half the house?!? How do I start?

See attached images for some idea of what the construction looks like.

 

[PO2]

Hello,
Interesting. I have a similar problem. But from what I can see, you didn't get any answers here?
How did you proceed?
You temporarily relieved from the inside and replaced what was needed of the rotten sill, I guess?
From the picture, it's not clear whether the upper floor rests directly on the plank wall or on a wall plate?
In similar houses, there can sometimes be iron fittings in the corners, did you find any such?