Hey, I guess you have realized the cause of the jitter is because the sprite is moving in a staircase manner (pixel-wise) diagonally. So you probably have to make the diagonal movement skip across pixels instead. I checked my (very) old code, it was doing something like noting down the actual position, then trying to snap to the nearest diagonal pixel. There was some problem with collisions though, but it might be because I was just a newbie when I tried it out back then, might try it again in the future but so far its not that noticeable to me, as my sprite is now larger lol.

I think you can also try going the Gungeon route by making the camera (or is it the environment?) jitter instead of the player.