I've never tried doing that but would think it's possible if the formats of the files are the same.
I've actually never looked to see what kind of format my iPhone uses for video.
I have 'mixed' videos from my A7ii and A7iii.
It would largely depend on what formats the software you are using can ingest. If it can pull in the video, you should be able to cut/copy/paste and trim out the video to whatever you need, then export it as one video. I have not edited video in some time but any of the software I've used in the past would have handled it, provided it was in one of the supported formats.