use drei/view for this. it is generally better to use a single canvas and split it with gl-skissor which is what view does for you. it runs faster and you can share resources (textures, materials etc) but each view still is isolated.
if you want to apply camera matrices you could, for instance, use the cameras worldMatrix or quaternion and apply it to the scene.
or, just don’t define a camera in the other view and makeDefault the control in the first and that’s it View skissor, same camera - CodeSandbox you can also put the orbitcontrols into the canvas as a direct child and it would affect all views.