I made a script to install all of your Non Steam Game Launchers on

Borderlands 2 Non Steam - Colaboratory

Heroic Games Launcher now on Flathub, even easier to run Epic Games on Steam Deck

GitHub - redromnon/HeroicBashLauncher: Directly launch any Epic Games Store and GOG game from anywhere without Heroic on Linux.

How to Launch Non‐Steam Games from Steam (Linux): 6 Steps

Steam Community :: Guide :: Making Non-Steam Games Show Up In Your Friends List

Steam Community :: Guide :: Run Games from Battlenet Launcher with Steam Overlay

How To Add Epic Games Store Games To Steam - Cultured Vultures

Steam Topluluğu :: Rehber :: Making Non-Steam Games Show Up In Your Friends List

Get Battle.net, EA, Epic Games and more on Steam Deck the easy way

NonSteamLaunchers v1.1 - Update now includes Games, The EA App, and Itch.io : r/SteamDeck

How to Install 3rd Party Launchers on the Steam Deck the Easy Way! - Steam Deck HQ

Easy Launcher installs on Steam Deck - Epic Games Store, Batttle.net, Ubisoft Connect, etc.

Playnite Launcher: Automatically search Fitgirl, and other download sites for all your games! : r/PiratedGames

How to Install 3rd Party Launchers on the Steam Deck the Easy Way! - Steam Deck HQ

Install Third Party Game Launchers On The Steam Deck Easy