It becomes hard to discuss "1Password for Linux" without knowing if you mean 1Password.com or the old 1Password, with .opvault locally and/or synced to Dropbox-esque

However, if it's the latter, KeePassXC now knows how to read the .opvault format: https://github.com/keepassxreboot/keepassxc/issues/1462 I could imagine teaching it to write their opvault file format, too, but at the time it wasn't a use-case that I needed

I would actually suspect teaching KeePassXC to read the 1Password.com cached vault would be even easier, since they now use sqlite3 for storage, but it would still -- afaik -- be confined to your local machine since their web API is undocumented

There is also a command line application: https://support.1password.com/command-line-getting-started/