There's a merged pull request on the void-packages repository

connman: allow members of network group to control daemon via dbus
https://github.com/void-linux/void-packages/pull/21618

Description:
The change enables users of the the network group to use every ui available for the connman daemon. I tested connman-gtk, connman-ncurses, connman-ui, econnman and cmst.
Configuration is based on the wiki article: https://wiki.voidlinux.org/Connman