Chandelure for B- Rank:
Chandelure is, as a fire special sweeper, outclassed by Yzard. However, Chandelure has a few very good niches.
Flash fire and infiltrator are both very good abilities, with the former allowing it to switch in on Yzard, and fire back with sun and flash fire boosted fire blasts making it a good counter. The latter allows it to hit sub mons hard, like kyurem-b.
It is limited to a scarf however if it wants to compete. Still, it has a good movepool that includes shadow ball, psychic, and energy ball, making it versatile.
Crawdaunt for B- Rank:
Crawdaunt's adaptability knock is something to be feared. Held back by its extremely low speed and frailty, crawdaunt attempts to make a name for itself by boosting with swords dance and smacking the meta hard with aqua jet, knock off, and crab hammer. It is a great rain sweeper, but again, outclassed by more reliable water and rain sweepers.
Darmanitan for B- Rank:
Powerful physical fire type? Char X comes to mind immediately, followed even by choice band entei who isn't as powerful, but has sacred fire, good bulk, and extreme speed. So what darmanitan offer? Immediate brutal powerful. Sheer force flare blitz is no joke, and with base 110 HP darmanitan doesn't fear recoil as much as other Pokemon. U-turn gives some prediction breathing room and rockslide and superpower are great coverage moves. Fast hyper offensive teams might even prefer it over other physical fire types due to its ability to immediately and brutally damage the majority of the metagame.
Sharpedo for B- Rank:
Speed boost is a great ability, and physical water types are not exactly common. While its sets are rather predictable, it doesn't matter if it still gets the job done.
Just found out that Adamant life orb aqua jet fails to OHKO even 4 HP talonflame. That's so damn disappointing.