ScraftyIsTheBest
On to new Horizons!
Yeah speaking in terms of in-game playthroughs Cinderace is actually my least favorite of the Galar starters to use in-game in SwSh. Its in-game movepool is pretty shallow, as aside from Pyro Ball which has low PP the best things it's got are stuff like Bounce and Double-Edge, which are lame, and a lot of the physical moves it learns by TR/TM and level-up are either not impressive or don't do much to supplement Cinderace in terms of coverage. It's a very one-trick pony in-game as its best use is really spamming Pyro Ball, which is fine, but not all that fun.I'd argue the lack of a secondary typing and being a physical attacker makes Cinderace straight up worse than Blaziken or Infernape for an in-game playthrough. Libero is a non-factor for most of the game (unless you get lucky with wonder trades) and you barely get any strong moves besides Pyro Ball, which imo is a fairly mid move for an in-game run due to its low PP. High Jump Kick isn't an easy move to get due to the breeding requirement and Gunk Shot requires grinding for raids or getting lucky with TR salesman in the wild area, so most players will be stuck running weak moves like Double Kick, U-Turn, etc. for most of the game. You at least get Acrobatics in Ballonlea as another strong move, but frankly, its not gonna be too good vs Cinderace's worst match-ups like against Rock-Types.
Despite Cinderace having the edge competitively, in-game I find Rillaboom and Inteleon a lot more fun to use. Rillaboom has a weaker signature move in a vacuum but it also has a high BP physical STAB to abuse in Wood Hammer (which also has more BP) as well as colorful coverage that compliments its Grass STAB very well, such as Ground coverage moves like High Horsepower or Earthquake, Acrobatics, Knock Off, and whatnot, and it also has some good boosting moves in Bulk Up or Swords Dance to help it, so with those tools it is quite fun. Inteleon doesn't really get good until it becomes Inteleon, but it has a good STAB and it also has a pretty colorful set of coverage with Ice Beam, Shadow Ball/Dark Pulse, Air Slash, Mud Shot, and so on. Both of them have more enjoyable movepools for an in-game run and are far more fun to use than Cinderace in-game imo.
Funny thing is, Charizard and Greninja despite being the most shilled members of the Kanto and Kalos trios, respectively, are really also not that much more impressive than the other members of their trios in their respective games for in-game playthroughs. Charizard in RBY is hilariously bad as it's stuck with Ember for a long time and has to wait until it gets Flamethrower at Level 46, and is forced to rely on physical coverage with Dig and Slash for a while, meanwhile Venusaur has a great early start, gets a strong crit move with Razor Leaf, and is a defensive behemoth in the late game and Blastoise is consistently good thanks to consistently having good STAB for various points of the game and having the most consistent overall performance in-game. With XY, Greninja actually isn't all that impressive without Protean as it's basically a fast Water-type with good STAB and a good second type in Dark combined with a decent coverage movepool, which makes it a good fast attacker, but its in-game performance in its own game isn't any better than, say, Feraligatr, Empoleon or Samurott in their own games. Certainly not on the level of Swampert or Primarina who are powerhouses in their regions. Delphox is actually more impressive in-game than Greninja because Fire/Psychic STAB is great, and it has Calm Mind and good special firepower and bulk to make it a murdering machine late game, meanwhile Chesnaught is reliable with good bulk, a good offensive movepool and boosting moves, and some defensive tricks if you want to use it as a tank/staller, making it fairly interesting and versatile in-game.
Like yeah the likes of Charizard, Greninja, and Cinderace have tools that make them shine more competitively but in-game none of them actually stand out that much in their own respective regions, they're not really any better than their counterparts in any notable way.