I recommend Arq also at least for Windows (have not tried on Mac). I'm using Arq 7 cloud (something like $60 a year) on a Windows desktop. The software is straightforward, generally stays out of your way, gives alerts when needed, reliable, saves versions similar to time machine, fairly configurable, and backups are end to end encrypted, and can be saved to Arq's own cloud service, any local media, and most other cloud services. I had lots of permission errors when starting for a small bunch of files but was able to fix them out by either resetting permissions or excluding files (e.g., caches). I think these are the kind of problems you can expect on Windows when using Shadow copy, no reflection on Arq.