2D terrain texturing with submeshes?

Hello everyone,

I'm trying to make a terrain, just like Prison Architect does. It's not like Minecraft just blocks of textures aligned perfectly side by side. I want the textures to blend.

I was thinking of submeshes, but I haven't worked with them yet, so I can't say if it's the right approach. I've read about drawcalls for every material, so this is probably not a good solution for a terrain with obviously many materials.

Maybe someone can get me on the right track, as I'm not looking for a pre-made solution.

Thanks!