EDIT: because there is not a lot of information about how to create a flipper font, below is a step-to-step guide for FontLab. I hope people with no background knowledge, and with the same questions as me can find some answers. My original message and questions about a flipper font are shown below.
A flipper font is a font that has multiple variations of every character. These variations are alternately called upon to bring more variations inside the font. Example:
this is the default behaviour, on the keyboard the ‘n’ is ticked, and the same 'n' is used again and again.