ALSV4_CPP Overlay Menu UI - TwitchBlade/ALS-Wiki GitHub Wiki
The overlay menu key is set in DefaultInput.ini:
+ActionMappings=(ActionName="OpenOverlayMenu",bShift=False,bCtrl=False,bAlt=False,bCmd=False,Key=Q)
When this is pressed it goes to ALS_PlayerController InputActionOpenOverlayMenu which is responsible to create the widget and display it on screen.
You need to keep Q pressed to show the menu.