With cannival perk can i eaten them?

No that perk only allows you to eat human not ghost.

Hahah! But that's actually a good point, Ghost People are considered "creature" rather than human by the game, and more specifically "Abomination" (They count toward the Abominable Perk/Challenge).

My question is, since they seem to be a lot like Feral Ghouls (their flesh is like glowing ones, and they glow like glowing ones), can you eat them if you have the Ghastly Scavenger perk?

It would be cool if you had the Ghastly Scavenger perk to get a unique dialogue with Dog where you can discuss the finer points of dining on Ghost People.