Without the hideIntelGpu flag, the game did not boot. There was an error:

Assertion failed: IsValidIndex(Index) [File:D:\build\++UE5\Sync\Engine\Source\Runtime\Core\Public\Containers\UnrealString.h] [Line: 218]
String index out of bounds: Index 0 from a string with a length of 0

Since most people have an actual graphics card, this is probably not a common issue.

In-game settings are very limited. There is no way to change from full screen to windowed in game, nor to change the display used if there is more than one available. I added -windowed to the launch command to let me move it to a different display.