if you use an AOSP based ROM, give Seedvault another look since they merged device2device-transfer in the beginning of the year https://github.com/seedvault-app/seedvault/pull/562
I think it was back on LineageOS 16 that it was actually broken for the entire release. It wasn't even possible to do a basic backup at all.
Google for "site:reddit.com does seedvault even work" for dozens and dozens of examples.