Selfhosted or not, you can also make keepassxc portable with a usb drive.
Here is a old thread from redit explaining how to do it:
Dude.... KeepassXC has portables for linux, there is no need to mess with wine or mono. As long as you have both portable versions of KeepassXC, you will not have a problem. You can totally have your database sync between OSs.
- For Linux, just get the AppImage for the portable.
- For Windows, get the Portable ZIP archive.
- Shove them both into a USB, you have KeepassXC portable for both OSs on a stick.
Source: https://www.reddit.com/r/KeePass/comments/10i8joq/keepassxc_portable_on_windows_and_linux_or/-