I did heavily reference Kaiyuan Tongbao/開元通寳 when drawing the coins so please keep it in mind if you consider historical accuracy important. It might also look a bit thick...
Showcase in color

This image^ was made when the angle dynamics are set to "direction of pen" usually it's just vertical when using, so if you want to tilt it like I did in the image above, change the "none" to "direction of pen" in angle dynamics
Showcase of pens (front facing)
I included a brush without the "string" in the middle in case you wanted it
please note that: in order to make that stack of coins on the bottom right, you have to go to angle-> angle dynamics-> and turn off random
There is pressure:

The more pressure, the more it looks like a circle. The less pressure, the more it looks like an oval. It also becomes more spaced out the more pressure you put down
Showcase of pens (sideways)

There's also pressure for this pen

The more pressure you exert, the more the "string" inside of the coins will be visible
I've also included some color jitter on the coins, since I didn't quite perfect it, feel free to mess around with it however you like
You can also change the color (it depends on your main and sub color)
Update: added a new brush without the harsh shadow

it's also using "direction of pen" angle, I use this to draw coins facing downwards instead of being held. this also has slight pen pressure on it so you can imitate perspective (cool)
Let me know if you have any problems ^^