For the most part, Rosalina's all agree that she doesn't seem to get much out of custom moves.
This means for the rest of the cast, they're usually improving their match ups with her with customs, while Rosalina has no such options.
Several characters have longer range tools that allow them to break the zoning of the campers with success on their customs. Speed Drill on Meta Knight has great priority, amazingly fast and much longer range. From the other side of the stage you can punish people lagging just because that move exists. He would otherwise not have an option which the opponent is forced to respect, making the neutral game between them less one sided, and hence an over all better match up.
Unfortunately for MK, Luma can take the speed drill hits for Rosalina (each individual hitbox on the move can be cancelled like a projectile), making it less restrictive than say Marth's Dash Assault (neutral b replacement) which allows Marth to do the same thing with the same speed, but slices right through Luma and challenges rosalina with transcended priority.
In Marth's case, without dash assault, Rosalina would be a very complicated match up, with her neutral being excessively better than Marth's default, and her play style revolving around just running away and keeping him out, he is forced to approach her. With Dash Assault I genuinely ignore Luma and get a free hit/approach/advantageous position on her every time she uses a move that's within 1/3rd of FD of me (because her frame data by herself is not safe). Because of this she's forced to respect how quickly I can capitalise on her and cannot afford to whiff attacks on me. A huge match up changer.
This means for the rest of the cast, they're usually improving their match ups with her with customs, while Rosalina has no such options.
Several characters have longer range tools that allow them to break the zoning of the campers with success on their customs. Speed Drill on Meta Knight has great priority, amazingly fast and much longer range. From the other side of the stage you can punish people lagging just because that move exists. He would otherwise not have an option which the opponent is forced to respect, making the neutral game between them less one sided, and hence an over all better match up.
Unfortunately for MK, Luma can take the speed drill hits for Rosalina (each individual hitbox on the move can be cancelled like a projectile), making it less restrictive than say Marth's Dash Assault (neutral b replacement) which allows Marth to do the same thing with the same speed, but slices right through Luma and challenges rosalina with transcended priority.
In Marth's case, without dash assault, Rosalina would be a very complicated match up, with her neutral being excessively better than Marth's default, and her play style revolving around just running away and keeping him out, he is forced to approach her. With Dash Assault I genuinely ignore Luma and get a free hit/approach/advantageous position on her every time she uses a move that's within 1/3rd of FD of me (because her frame data by herself is not safe). Because of this she's forced to respect how quickly I can capitalise on her and cannot afford to whiff attacks on me. A huge match up changer.