Testing EOS multiplayer locally is more tedious than it should be. You need a separate Epic account per test player, the DevAuthTool running with a credential for each, and then every single test means launching several standalone clients by hand with the right command line arguments. Before any of that there is the EOS config itself, where a wrong section name or a missing line fails silently and costs you an afternoon.
I built a plugin to remove most of that. Free, source available, and editor only, so nothing from it ships in your packaged build.
[screenshot: Quick Launch tab]
Quick Launch starts 2 to 4 standalone clients, tiled, each its own process with its own EOS login and its own log file. It passes the stock AUTH_TYPE / AUTH_LOGIN / AUTH_PASSWORD switches, so any project that calls IOnlineIdentity::AutoLogin picks up the right account with no extra code.
Setup writes your credentials to DefaultEngine.ini and fills in every other line EOS needs: DefaultArtifactName, bUseEAS, bUseEOSConnect, the overlay flags, DefaultPlatformService, and the net driver definitions. It only adds lines that are missing and never overwrites values you set yourself.
Validate runs 12 checks for the usual pitfalls. AuthScopeFlags crashing EOSShared on startup, a bare [EOSSettings] section instead of the full path, DefaultArtifactName not matching your Artifacts entry, NetDriverEOS configured but never winning because the ClearArray line is missing, and so on.
[screenshot: Validate tab]
Package handles the post-package step for the EOS overlay in shipped builds, generating Play.exe through Epic’s bootstrapper tool.
Requirements, so nobody is caught out:
- UE 5.7, Windows
- Your game needs to call
IOnlineIdentity::AutoLoginsomewhere, which is the standard EOS pattern - The DevAuthTool still has to be running with credentials named to match. That is Epic’s tool and I cannot redistribute it, so there is a Dependencies folder you drop it into
- You still need a separate Epic account per test player. Nothing gets around that
License is source available. Free for commercial use, including shipped games, studio work, client work and paid services, and anything you build using it is entirely yours. The only restrictions are on the kit itself: you cannot resell it or pass it off as your own.
Happy to answer questions here. If you hit an EOS problem the validator should have caught, tell me and I will add a check for it.