Have submitted one image. Please advise if this what you require. Are you allowed
to use images of these characters?

Great question. I am using the images in fanart and fantasy trading pins, so there isn't an issue. Thanks for asking.

Intresting project. I would like to participate.
Just one question to make it clear for me - the lines must be at least 0,4 mm thick? What is the size of the pins then?

2.5 inches roughly.

Thank you!
Also, the pins should'nt be circle, right? They can be outlined as a figure of a characters? And the characters must be drawn in full height?

They don't need to be circle, but can be. The manufacturer can cut them to fit the drawing exactly.

Thank you very much for answers. I will try to do my best here.