Detail this asset from Unity Asset Store: Original Link
This is a paid asset, but we’ll share Mesh Slicer Free for you. Enjoy!!!
Mesh Slicer v2.0.6 (Latest version)
Mesh Slicer v2.0
– Synchronous/Asynchronous slice;
– Slice meshes with colliders converting BoxCollider, SphereCollider and CapsuleCollider to MeshCollider;
– Skinned mesh support (beta version)
– Easy to extend;
– Very fast algorithm (just take a look at reviews);
– Smart optimization. So after slice you will not see any redundant triangles or vertex due to slice;
– Slice by plane;
– Slice by knife (examples).
The game that uses this asset (android): BeSlicer
Documentation
You can try it for free here. This is fully featured mesh slicer, but with no source code (dll-s only). And it will not work in release mode more than one minute.