How to change meshcollider thickness

I want to create 2D game objects with “thick” meshcollider from below:
[16449-未命名-1.fw.png|16449]

Please help me!!

It seems you can attach the mesh renderer to one object, and the mesh collider to another object, which have parent/child relationship in the hierarchy. Then you can scale one of them and not the other. In your case you’d want to scale the collider larger than the renderer in the x axis, so that it pertrudes in left/right of the rendered mesh.

See here for some illustrations of how this can be done:

Instead of trying to use a mesh collider, you should use a box collider. That way you can scale the collider on all three axis around your object.