Fascists want debate because they want their ideas normalised. By "debating" them, you put their ideas on a level playing field with your own. If you agree to the debate, the fascist has already gotten what they want. The actual debate itself is irrelevant, they just want legitimacy and attention directed at their toxic ideas.
Especially don't debate them in a sphere where they control the mute button, they have the majority of audience, and their voice is louder than yours. That's not a debate, that's you being a prop to be scolded and laughed at.