Vertex Painting Equivalent

I’m trying to make a good looking map for my game, but want to add a muddy path to the sand ground that is seamless, which is difficult, anyway, what I am asking is whether there is a tool that works on parts (not terrain) to paint them seamlessly, that works similarly to the one in Source (2) Hammer.

Toolbox has models people create so you could use an asset pack that is open-source or either learn Blender to make the model in however detail you’d want it to be.

Just use roblox’s marerial generator, use keywords , seamless , 2d, topdown , tileable, them use it on flat parts, unions or meshes… or z idex some surface textures / decals…

What about a having a Decal of the path and applying that to the ground part?