I don't think the author has ever seen Crush magic, nor has he even read the wiki. His version is pretty much just One for All from Walmart
Ilovefics
43の人に「いいね!」しました
いいねFrom my perspective though, there are similarities between the two. Mostly their destructive prowess is identical, though Crush has some differences with One for All and I tried my best to add that aspect to this story. Such as the MC can destroy anything he comes in contact with, that's why in many fights he only uses his fingertips to fight, it does come off as a rip-off since Midoriya had the same problems with trying to control his quirk. But if I add, even Gildarts himself has trouble controlling his signature magic due to its destructive abilities, in the latest chapter I did add some properties, such as when Gildart's magic hits a human it could split them apart into mini versions of themselves (if he unintentionally or doesn't hold any malice against the person) I toned the MC's quirk cause I read that in many wiki's that if Gildart's is unfocused he could destroy or smash anything he come's into contact with. Many heroes in MHA have some setbacks, though I would love Kazuki to be an overpowered character, his quirk can tilt the balance of the MHA world, I did do my research and watched the Fairy Tail anime, though I don't remember the whole plot since it's been years since I rewatched the anime. Before writing this fic I did my research and entered many wiki sites trying to fully understand Gildart's magic, but it seems like I was lacking in adding such aspects in the story since it comes off as a Walmart version of One for All. I deeply apologize as the author for making it look and seem that way, I'll refine such aspects and emphasize the difference between One for All and Crush.