How to make these skin pressures?

This artist uses Blender and Marvelous Designer, and uses soft body for the jiggles of the whole body.

How to make this pressure by clothes?
Looking at this artist’s other works, it seems that this pressure was not sculpted.
Aren’t the clothes in the compression area too clean to be sculpted?
Probably used soft body, but I don’t know how to implement it specifically.

My guess may be wrong. Please advise.

Looks like sculpted deformation for me. Not clothing, just the body. It would be insanely computation intensive otherwise

use sculpt tools. Subdivide the mesh using multi-res modifier (3+ subdivs are ok), switch to sculpt mode, go the part you need. Use M for “mask” mask the area you need, press CTRL+i to invert the mask.
Switch to INFLATE brush, adjust strength, go close to the parts you need and start using the inflate brush on them. To smooth, press SHIFT while you sculpt. If smooth is too strong, go to the smooth brush and lower the strength. go back to inflate tool and continue to refine with softer smooth.
If you press CTRL instead of Shift, the operation will invert for any brush. Instead of inflate, you’ll make a hole.

(I added one more image to imgur.)

As you said, it seems that the skin is inflated, and in addition to that, the part of the clothes to be pressed seems to be pushed in a little.
The reason I’m confused is because of this part.

Obviously, at least in Blender, after adding softbody to the character and collision to the clothes and simulating it, Blender freezes.
(Ryzen 3700X, 32gb)

The cloth brush in sculpt mode can do the same, no need to “press play to simulate”.
No thanks.
No “I will try”.