My guess is that it’s your floating rotors. Those inexpensive Chinese rotors are very noisy since the tolerances between the disc, carrier, and the buttons they use aren’t super tight.
Could also be the front pads knocking since they can shift around in fixed calipers. The pads will settle in one location, then when you grab a handful of front brake, the pads are pulled into a sudden stop at a new position within the caliper which creates a knocking noise. You can confirm this at walking speed - walk your bike backward with no brake on, stop with the front brake then walk forward and stop again. If it’s the pads shifting, you’ll hear and/or feel it. The Brembo 6 pot race brakes on my Subaru track car back in the day did this every time I stopped and it drove me nuts. Nothing to worry about mechanically typically, but it is annoying.
Or, it could be a combination of all things.