Hi @Kaese! Welcome to the salt mines forum!
First off, this might be a bit off topic, but it sounds like you’re doing a calibration with hot hotend? I can’t think of any good that comes from that, although I’m open to discussion on this - I haven’t really thought of it before.
If you take the X axis off the Z towers - do both Z modules move?
Overhangs could be an insufficient cooling issue - to test that, put a desk fan next to the printer while the overhang is printing. At least for me, that helped.
Stringing and bridging could be a temp issue? If you have some non conductive heat stable thermal paste put some in the thermistor hole, it’s just sort of floating in there. Staff has doubled down in the past that a floating thermistor is totally fine, but many people had issues with it. I also put some in the heater cartridge hole.
If you’re comfortable tinkering with things, these modules are quite easy to open. Check out here: Rail module exploded diagram?. While you’re in there, definitely make sure there’s a piece of silicone thermal pad on the chip, some are missing it, which is super bad.
You could also pick up some plastic grease for the modules if you want, like this: How to maintain the snapmaker in perfect condition?. A bit above there staff posted a video on how to apply the grease: How to maintain the snapmaker in perfect condition?.
Also, if it’s not obvious (it wasn’t to me and I didn’t see it in any documentation), the weird spring tool in the provided toolbox is for tensioning the dust covers during reassembly. There’s a video they posted, can’t find it at the moment. Also useful if it vibrates loose and just needs a tightening because it’s starting to make noise when the steppers move. I guess they don’t use it all the time, not 100% on when it should be used.
I’ll keep this as short as possible, but there’s lots else to say. One final thing: the z probe is inductive, and is detecting the presence of the spring steel inside the removable print sheet. If you switch to glass or something non-conductive, or even something conductive but further than about 1mm away from the sensor (like an aluminum bed with a 1.5mm print sheet on top like someone else here in the forums), the nozzle will crash into the bed while probing.
EDIT: Also just found this topic, newer than yours by just a bit. Going to follow this one too, sounds like it could be similar? Grinding noise upon saving Z axis calibration