When putting this back in, watch out because it might have gotten flipped around, especially if you kept the ZR cable attached as I would recommend you do. Probably obvious, but it threw me off for a few minutes.

Just adding to the swarm but you do NOT need to do this step. Just be careful and mindful as you keep it off to the side. If that's difficult for you it might be easier to go through the (apparent) hell of taking it out and putting it back in, but for me it made more sense to just keep it in and be careful.

Like the battery, don't unplug this if you can avoid it. It's easier to put back together if you keep things as attached as possible (though it can be a bit cluttered while you're doing the repair)

This step was basically necessary for me to get this plastic plate out, but you don't have to do the unplugging in the next step.

Echoing a lot of other comments, but yeah you don't need to remove the battery, even if you're new to this. These Joy-Cons were my first repair and you'll be fine just keeping the battery off to the side as long as you're careful.

This is probably very obvious advice, but it takes a decent bit of pressure to get these screws out. Hold the controller and support under where the screw is with one hand while applying a good bit of downward pressure with the screwdriver in the other hand. Don't go crazy, but you don't have to be delicate. This was my first repair and this tripped me up for way too long.

It was a bit difficult to get the new joystick into the hole, but I was able to just push it through. Your mileage may vary.

I didn't have any issue taking this out and reattaching it later; I pretty much had to do it since the ribbon cable ran right over the screw.

You're a real one for this, thank you

Definitely took a lot more effort than "flipping a page." Make sure you loosened the screws correctly but if you did you might need to give it a strong tug. Mind the ribbon cable.