Transfer Mail App data from iphone 12pro to 16pro

Just upgraded from 12pro to 16pro. Most of my old emails did not transfer when I did a backup/restore. I backup locally to my laptop using itunes. Our email accounts are POP so local data does not mirror what is on the server. Deleting and reinstalling accounts will redownload everything on server, not the curated set of emails that are reside locally on my old iphone. Is there a way to copy the mail data file that the mail app uses from my 12pro to the 16pro so that the new phone email data file mirrors what is on my old phone? Can I connect my iphone to my laptop and search for a particular folder/data file on iphone as I would another external device? Can I then replace the corresponding data file on the 16pro?