This look like a bad sway bar bushing?

https://imgur.com/a/DSvdPM7

Seems split in parts. The opposite side doesn't have this.

Suddenly getting a lot of noise metal on metal scraping) on low speed turning and going over speed bumps on the side with this bushing

That's not terrible, but not great. Replace them and check your endlinks as well.

Agreed, that is due to be replaced.
I highly doubt it would make a metal on metal sound though. Worn out endlinks are more likely.
Unless accident damage, I replace suspension parts in pairs. If 1 endlink is bad, do both now. The cost is not much and the car is up and tools are out.

Doubt the bushing is making the scraping noises though, they do make a creaky squeal noise when they're worn. As a test, you could unbolt one endlink and see if the noise is still there. Unbolt from the knuckle and ziptie the dangling bit to the bar; if the noise goes away, there's your answer.

No accident damage. I've had coilovers on the car for nearly two years, slight drop of 1cm and a non-aggressive alignment. Perhaps not upgrading the endlinks from stock was a mistake when getting the coilovers installed. Can't see anything obviously wrong with the endlinks on either side, only this worn bushing on the side where the noise comes from. I'll get it to my mechanic and see what they say. Thanks for the input all.

This would help.

I would spend some time underneath and inspect everywhere for wear marks. metal clanking would leave a mark somewhere.

The split is normal (assuming that's why you circled it), that's how you install the bushings on the swaybar. Funny thing, I just came here to post about my own swaybar bushing issue haha

Have you taken it to a mechanic? Is the problem caused by a damaged stabilizer bar bushing? My dad's car has the same squeaking noise but he didn't take it in for inspection. Maybe I should help him take it in for repair just to be safe.

agree with CabOoze. The split is how the sway bar bushing slides onto the bar.

The bushing might need some silicone grease, but other than that, it looks okay.

sure, after a while, those bushings will develop slop in them and new bushings will help keep the bar motionless.

Are there poly swaybar bushings from SuperPro for the WRX? The poly will be more firm than the OE rubber, and will be more difficult to compress when installing. Also, the poly swaybar bushing will require silicone grease to reduce squeaking.

good luck in finding the clunk sound.