One thing I would recommend is separating this difficulty setting into two independent settings. Players with motor, visual, or cognitive disabilities, or otherwise slow reaction times, might benefit from more forgiving QTEs, while still enjoying the strategic challenge and drama that comes from playing with lower character stats. Or vice versa, a player who's not strong in the game's strategy might want higher stats to compensate, while still liking QTE timings be tight enough to be challenging for them. By de-bundling the setting, each player can mix and match options to get the experience that's most comfortable and satisfying for them.
The separation can also help with communication. Each option becomes about one specific thing, so it's easier to convey. And by presenting the two settings side-by-side, the player can read cues from each to understand the suggested gradient between easier and harder options - so if one setting is vague on its own, the context from the adjacent setting can help guide interpretation.
You could also leverage colour language or emoji expressions to help sell this association.

Here I've used some CC BY 3.0 icons by Delapouite, Lorc, and Skoll, via Game-icons.net - if I've chosen the icons, colours, and layout well, I I won't have to explain which one means what. 😉