Alcremie isn't really usable in a serious OU team. As lame as it is, LO Clefable is a much better offensive fairy type since with its power, coverage and healing it can break through some pretty common cores and has very limited switchins. Sylveon is a good defensive fairy, being able to beat the aforementioned Clefable and other common special threats like Hydreigon and Dragapult. It also gets wish for team support.
Clef would use life orb moonlight + 3 attacks and sylveon would be wish protect hyper voice mystic fire.
Defensive Clefable isn't as good anymore but it's still decent and gets Stealth Rock, which you need.
Gengar is pretty fringe, nasty plot is it's only real niche and even then it's outclassed mostly by Polteageist as a sash set up mon and Aegislash as a general ghost type attacker. NP Gengar is a decent lategame cleaner but it does need NP.
Cinderace is better off being offensive utility rather than band. Pyro Ball Court change u turn and any coverage you want with Heavy Duty Boots is a great way to deal with hazards will still being on the offensive. Also having 3 choice Pokémon isn't super recommended.
Alternatively, make Corviknight into a defogger and remove Cinderace entirely. Replace it with a rocker like Tyran or sash lead exca. Or even keep Cinder and replace Corvi with Exca for offence or Ferro for defence instead. A few options for you.
Dynamax is banned in OU so you don't need to make anything gmax.
