I'm using photosync with photoprisim and it works fine to autosync photos off, with the only caveat being that i'll occasionally close the app and it won't run for a few days/weeks.
Not as seamless as iCloud Photos but it works great.
I use PhotoSync as well, I setup a shortcut/automation that runs it anytime I connect to home Wi-Fi, after a 30 second wait and SSID check to prevent false positives.
I still have to click the notification, due to iOS limitations but having the notification show serves as a good reminder to run it.
Not as seamless as iCloud Photos but it works great.