I haven’t seen Snapmaker PETG-CF or know if they have it, but I’ve enjoyed Elegoo PETG-CF and PETG-GF. BIQU Frostbite cold plate (Cool Plate (SuperTack) in Orca Slicer). I’m not a 3d printing pro, but it seems to me to print well, hides the layer lines a bit more, has a more matte look, and acccording to their specs has a little more heat resistance than standard PETG.
I use plain Orca Slicer and have just printed with the built-in settings they have for Elegoo PETG-CF (may or may not be the same as what they have for standard Elegoo PETG). I’m sure you could dial it in more with some calibration tests, which I hope to do soon.