The Linux Mint Distribution Development Team has published a monthly newsletter outlining its progress in dealing with backporting bugs and fixes.
In the bulletin is described and the peer-to-peer file-sharing tool Warpinator, which is now available as a Flatpak to be accessible to people running other Linux distributions.
"We are pleased to announce that Warpinator, a network transfer tool released with Linux Mint 20 and transferred to LMDE 4, is now available to all Linux users as Flatpak. If you are using Linux Mint 19.x or Linux Mint 18.x open the Software Manager and search for "Warpinator". 
If you are using another Linux distribution you will find the app like Flathub on address
https://flathub.org/apps/details/org.x.Warpinator
The app will help you share files between computers running different versions of Linux Mint or other distributions. You can use Flatpak and non-Flatpak versions of Warpinator on the same network without either problem.
