Lego Pirates of the Caribbean will crash. The first thing to do is install protonup-qt. Protonup will allow the installation of custom proton packages from Glorious Eggroll. GE-Proton7-37 is the version needed. Before starting the game, click on the gears icon -> properties -> compatibility. Check “Force the use of a specific Steam Play compatibility tool”. Under the proton drop down, select GE-Proton7-37. In the properties menu, click the “General” tab. Deselect “Enable the Steam Overlay while in-game.” Under launch options, put “-dxlevel 90 -32bit -heapsize 2048”. The game will still crash every so often but you will have long enough to complete stages. Maybe restart the game after saving a stage completion. Sometimes it is beneficial to just enter the lobby then quit the game and start the game again. That is recommended if the game keeps crashing as soon as a stage is entered or quickly into it.
This will not work. It is possible to modify a GE Proton version but Bungie will auto ban the player within seconds of being logged in due to their anti-cheat not working.