It is called picture-in-picture (PIP) and there are plenty of how-to's around if you search.
This one for example: https://youtu.be/Cy4Qck2Oy6w
The only problem I can see with a music video, is making a good audio track that syncs with the video.
edit: Painfully slow to render video. (Reminds me of back in the 90's I used to make VCD's on a 486 cpu. Had to run the encoder overnight
)
I would look for an alternative to openshot, going to be hours to render a 3 track - main track + two PIP's 3 minute test video.
This one for example: https://youtu.be/Cy4Qck2Oy6w
The only problem I can see with a music video, is making a good audio track that syncs with the video.
edit: Painfully slow to render video. (Reminds me of back in the 90's I used to make VCD's on a 486 cpu. Had to run the encoder overnight
)I would look for an alternative to openshot, going to be hours to render a 3 track - main track + two PIP's 3 minute test video.