Basic question re multicam 4K and 1080

Hi, I've quite a bit of experience with still photography and Photoshop, but I'm a beginner with video and Resolve.

For my projected use, what I want to do is to use a fixed main camera shooting in 4K and a mobile camera shooting 1080 (because it can't do 4K). I want to be able to crop in to some of the 4K footage, the other camera will not be cropped because I can get the framing right while shooting.

So I'm thinking the way to do it is to do the crops where I need to in the 4K footage, then downscale it to 1080, then I can add the other footage which is already 1080, edit it in as required and output a 1080 video. Is that feasible and if so, is it the best way to do it?

Thanks

Yes, this can be done, works fine, but depends on the ca eras involved. What are the two cameras you are using?
Cheers

The main camera is a Panasonic GH5, the other one is a Canon 70D