I use this too. Keepass on windows, keepassxc on Linux and keepass2android on Android, with the db synced to all my devices via Nextcloud.
The db is encrypted via a passphrase plus a keyfile that I copy manually to each device (that is, it's not synced with the db).
I used to do this and leveraged dropbox for syncing. At some point, dropbox limited my number of devices so I self-host bitwarden. So much better now, and my wife actually uses it.
I have a great fear of things like the Android/IOS app from the store being compromised, resulting in my passwords going to someone. Do you do anything specific to overcome such fear?