None of the flexible filament extrudes were to my liking so I designed my own. I used the aluminum extruder tensioner bar but the standard one should work as well, and it should work on all Creality printers that use the same setup as the Ender 3. I've been successfully printing some NinjaFlex (85A) and haven't have a jam yet so I know it works.
Please read all the notes first, as the part will not work without some post processing.
Recommend adjusting the bracket before adding any filament by tightening it just enough that the free floating bearing can easily move. Also highly recommend an extruder knob like this one https://www.thingiverse.com/thing:2776404 to make it easier to load and unload filament.