I’ve been using FreeOTP for TOTP tokens for the last few years. No issues. I wish it had the ability to export tokens, although I can see why they practically wouldn’t want to give that ability to clueless end-users.
I use to use TB for everything but, new corporate requirements mean I can no longer run a rooted phone. Less I use a second phone for work specifically but I have no desire to carry two around with me.
Haven't been able to find a way around of backing up my tokens. Though admittedly the use case is small anyway, the backups are only valid for the device that the backups are from. Though this is by design, of course.