I changed the design, to place an other brush inside and also replaced the metal wire to a silicon strip to remove any extrudate from the nozzle before brushing.
The silicon strip is 19x13x2mm and here is the brush i use:
https://ebay.us/rV8RmR
Here you can see it in action:
The author marked this model as their own original creation. Imported from Thingiverse.