When I audited the VPN implementation in GrapheneOS for leaks, I used Linux Mint as my hotspot. So that definitely works.
I created and enabled the hotspot using this:
sudo nmcli device wifi hotspot con-name wifi1 ssid PUT-SSID-HERE band bg password PUT-PASSWORD-HERE
sudo nmcli con modify wifi1 802-11-wireless-security.pairwise ccmp
sudo systemctl restart NetworkManager
Just make sure to disable the ufw firewall first, if you have it enabled, as I found it interfered with the hotspot.
I also found that the GUI for setting up a hotspot uses a legacy crypto algorithm GrapheneOS doesn't support, making connecting to the hotspot not possible. You have to set it up using the command line like above.
Also, of course, your computer must be able to run as a hotspot in the first place. As in the driver and hardware must support it.