Skarlet keeps bouncing between A and B in many tier lists
I don't have much time to grind this game as of now, but i can see reason why she is put on A and B often.
She is put on B because some think this is where she will be once players start to flawless block her gaps.
She is put on A because some think despite the flawless gaps she can still bypass with different moves in between like blood ball which makes her plus instead, stagger pokes and so on.
So far i really have no idea where Skarlet is on tier list, and i play mostly online, learn and i gather data, so far i think her hardest MU is Erron black, due the fact that he can absorb all her projectiles so he never deals with her, and up close he is a nightmare, while mid range he is also good, there is no part of the game where Skarlet outranges him so she is always at his mercy without a doubt, all others S tiers are all manageable.
Jade with lag its a nightmare, but when is reduced you can usually take advantage of that to counter play her much better no matter if you stay on distance or up close.
Her play is really straight forward, nothing too crazy but seems pretty effective, she has ways to hit you on every mistake and puts you back on starting point no matter how she hits you, either is with a string in the ground or with a jab anti air, and if a character has a huge disadvantage staying fullscreen this is pretty much a 6-4 situation for her.
Her plus frames nets her a small 50-50 game where she doesn't gain combos unless you try to disrespect her, but sets up 2 krushing blows by landing an overhead once, or by landing a thrown whenever she is that plus, and when both are set to happen on the next hit in case you are forced to guess between them, it sets up her hardest Krushing Blow to hit which is B1, 2, so you can't disrespect throw, and if you respect the overhead her lows will start to become much harder to deal with.
But where she really shines IMO, despite being fullscreen against most characters or mid range, is in the corner, if Skarlet corners 80% of the cast they are so dead, because there is no space to back up, she has all the range in the world to keep you cornered and tools to keep you there, do combos and anything she desires as much as she needs.