For ranged weapons, particularly in first-person mode, it'd be much easier to aim with the keyboard.
XR is a 3D game, not Doom. You need to aim high or low, it's not enough to turn your character in the general direction of your enemy. Also, there is no auto-aim, so you need to pinpoint your crosshair.
Is there a way to configure the game to aim using the keyboard (without strafing)?
You mean having 2 sets of keys, one for moving your character in the world (forward/backward/left/right) and another one for moving the crosshair up/down/left/right on your screen, gameboy style?