@Sinak Hi, I’m dedicated to provide tech support, but developers also help from time to time.
Regarding your question and as far as I know, unfortunately the GIF specification handled by Pencil2D does not support transparency colors (straight alpha).
Instead you would need to:
- Export a PNG image sequence with transparency from Pencil2D
- Import the sequence as layers into GIMP (Or Photoshop if you use it)
- Export the transparent Animated GIF from there.
If you don’t know how to export GIF form GIMP her’es a video I just found that could help: https://www.youtube.com/watch?v=5E2ZvtOOuh0
I’m not sure when Pencil2D will be able to export with transparency, but it’s been discussed in the past so hopefully it won’t take long to have this feature implemented, though i don’t know the technical difficulties involved so that’s why I can’t provide you with an time estimation.