Importing .obj without .mtl

I am trying to import a .obj file into Studio and I notice in the documentation that it’s necessary to import the .mtl file at the same time. However, none of the models I have downloaded from Sketchfab in .obj format have .mtl file included, just a separate folder of textures. I have tried importing the .obj along with all the textures but I get nothing. Can anyone advise please?

The reason I am using .obj formats as opposed to .GLTF where available is because I am hoping to create some 3D models from scanning software in .obj format so I wanted to be aware of how to import/ any pitfalls beforehand.