Try givin a look on the web for some foss vpn client for android which supports port forwarding.
Maybe you should find some guides on how to setup multiple of them too with work profile or just port mapping.
Explained: How to run 2 VPNs on Android simultaneously
I had been looking on the internet a method that would enable me to run 2 VPN apps on the same device simultaneously, but just got to solve this.
My setting: I was trying to route all my firewalled traffic (ReThink Firewall) through a proxy to another vpn app. Psiphon Pro (FOSS) can accept traffic from inbound proxy but itself establishes a VPN profile and thus the firewall can’t connect (which too requires to function as a VPN).
VPN app in main profile: Rethink Firewall (FOSS, Fdroid)
VPN app in work profile: Psiphon Pro (Free VPN, Playstore)
Shelter app lets you clone apps using the work profile feature and takes only a few MBs
I used this setup on Android 13 and it works.
Solution:
Using the open source app, Shelter (Fdroid) create a work profile. A work profile can have its own VPN app running along with main (personal) profile’s VPN.
Install and configure the Rethink Firewall on Main profile.
In Shelter, set the Psiphon app to “Allow Cross-Profile Interaction”
Run the Psiphon VPN (app that would accept inbound traffic). In its logs section, see the SOCKS proxy port.
Set the proxy port to the same in Rethink Firewall in the correct way. As, 127.0.0.1:{port}
Now Rethink Firewall is able to tunnel all its traffic into Psiphon Pro (running in work profile)
My setup is TrackerControl + inviZible Pro.
Try givin a look on the web for some foss vpn client for android which supports port forwarding. Maybe you should find some guides on how to setup multiple of them too with work profile or just port mapping.
Thank you! That was enough information for me to find this guide: https://www.reddit.com/r/androidapps/comments/1j74tv0/explained_how_to_run_2_vpns_on_android/