Sorry, it was not supported yet.
If you must use your mobile phone to access it, you will have to use a manual configuration solution instead of S2S.
The configuration file is usually edited with the vi command.
vi /etc/config/wireguard_server
If you are not familiar with vi, it is recommended that you change the ssh tool. Some ssh tools support opening and editing files in a graphical interface. For example MobaXterm.
That requires the routing table to be set up manually. It is very complicated.