Use pass with a secondary location (e.g. ~/.password-store-perso)

.bashrc

# Pass with specific location
_pass-perso() {
  PASSWORD_STORE_DIR=~/.password-store-perso/ _pass
}
complete -o filenames -o nospace -F _pass-perso pass-perso
pass-perso() {
  PASSWORD_STORE_DIR=~/.password-store-perso/ pass "$@"
}

browserpass-perso

#!/bin/bash
PASSWORD_STORE_DIR="$HOME/.password-store-perso" $HOME/bin/browserpass "$@" <&0

com.dannyvankooten.browserpass.json

{
  "name": "com.dannyvankooten.browserpass",
  "description": "Browserpass binary for the Chrome extension",
  "path": "/home/raphink/bin/browserpass-perso",
  "type": "stdio",
  "allowed_origins": [
    "chrome-extension://jegbgfamcgeocbfeebacnkociplhmfbk/",
    "chrome-extension://klfoddkbhleoaabpmiigbmpbjfljimgb/"
  ]
}