I used cloth for physics, but it didn't work well when objects collided, can anyone share some experience?
I can't share much experience but I looked through and found solutions specifically for collision in Blender in this tutorial:
12 minutes, almost no dislikes (the YouTube terds enabled dislikes again), worth it and to the point. Good luck, bro
It can be tricky, but I'm guessing you tried to have it interact with rigid bodies which is not how cloth physics work. You need to add a collision modifier to the object for them to interact with the cloth physics. There are also lots of other best practices and things like using proxies and surface deform modifiers but you'll need to be more specific for anything useful.
The video that Antichrist linked to is pretty good if you want to get a very basic feel for working with cloth physics on MMD models, but it's actually not that great of a method in my opinion. It's generally much more efficient to have one model with uniform topology that you run as a proxy to simulate cloth physics and then you bind your visual meshes with a surface deform modifier to that proxy. There are lots of benefits to doing it that way, but it's not necessary to worry about it on simple simulations so if it sounds too complicated or you aren't going to use cloth physics very much then it's not a big deal.
Also as an example, I used the proxy object cloth simulation method in my latest video (Rin Dive Dance).
I know a few MMD'ers (including some who use Blender). Maybe they can help you...
I used to have a lot of contacts among Japanese MMD'ers, but now they almost all ignore me unfortunately! :(