I was using this app until I created a new gpg key and OpenKeychain did not work because of this https://github.com/open-keychain/open-keychain/issues/2886. I then installed password store inside termux and I am using it as if I am using it from my PC. That works pretty well.
Since I switched to Wayland, I could not find an alternative for barrier that I used under X. After a lot of search I bumped into a project called rkvm. You can check it out. It is a bit more difficult to setup than barrier but it works pretty well for me.
The only bad thing is that both computers must run linux.
It’s not about secrecy. It’s about privacy.
https://wiki.termux.com/wiki/Termux-clipboard-set