Well… I’m here to show a test with multiple softbodies interacting and it looks right for me… a little jittering but this effect is the same with cloth modifier but I can get rid of it by increasing the quality steps of cloth simulations and cloth collision quality as well, maybe increasing the steps of the solver here will also work but there’s another issue… This simulation took almost 4 hours!!!
I will share the original simulation test I did but using blender cloth with pressure(after almost 4 hours o baking I noticed that the upper cube needs to go down a little further)
In this example all spheres are merged in the same object and they collide by self-collision: