I use Vaultwarden hosted on my private server. It's great, will never use another PW manager. and yes it's cached locally so you're good. on PC, at least via the bitwarden CLI, you do a one time login and that's it. you're logged in until you tell it to logout, logs you in automatically on restarts and what have you. plus it's very easy to access on whatever pc or phone you want to use. for pc you can just add the bw extension and have your passwords where ever or just simply login to your vaultwarden page remotely. this has been a life saver for me a couple times when I needed a pw for something but I wasn't on my machine and borrowing someone elses.

tl;dr: yes, credentials are cached locally. https://github.com/dani-garcia/vaultwarden/discussions/4676

The major downside to the single file storage used by Keepass is that it's easy to accidentally create a conflict between files on different devices if they're not synced immediately. Conflicting files have to be merged manually or data might be lost. I've run into this several times with Keepass + Nextcloud. In comparison, a central master database with local cache can resolve conflicts between individual records.

Why do you want to ditch KeePass? I use it with Syncthing between at least six different devices without an issue.

Do you worry about the sus new maintainer for syncthing-fork on android?

And, i can't find clients on f-droid. Any variants recomended that dont come from the playstore.

Another key feature will be Keepass data import.