UE4.27 LAN Multiplayer Sample
This is just a sample, an .apk extension to install and test how it works. There's no need to set up anything. First player to run the game becomes the server, all the other ones will join as clients.
Have access to the template files here https://www.3dmantovani.com/game-props-1/ue4.27-vr-lan-multiplayer-template