# 1. Create a repository index in the directory containing the file
xbps-rindex -a /home/void/appimage/onlyoffice-desktopeditors-9.4.0.129_1.x86_64.xbps
# 2. Install the package using the directory as the repository (-R)
sudo xbps-install -R /home/void/appimage onlyoffice-desktopeditors