Self-hosted instance of Bitwarden works pretty well, and you can make it accessible behind a VPN to your local network only (plus there are multiple implementations of its back-end). Less-automated solutions make impractical concessions in usability.

Reference impl. in C#: https://github.com/bitwarden/server

Self-host friendly impl. in Rust: https://github.com/dani-garcia/vaultwarden

p.s.: reference implementation is by far one of the better examples of how to do microservice-based C# solution of high code quality right.