I mean, not quite. What she likes, at least based on what she's been thinking for now, is not bullying her, but rather seeing her happy. She's not (yet?) awakening to sadism, she's awakening to yuri.
This is definitely true, and while it's funny to imagine this manhua as a retelling of The Real Her there's very little evidence that Elsa is a real masochist and even less that Evie has a subconscious penchant for sadism. It's the system that's forcing them into those roles... and since they are falling in love with each other while at the same time having no choice but to engage in bullying games, it's only natural that some confusion arises.
I also don't think that Elsa and Yvonne are truly masochistic or sadistic: instead, their "bullying" is more of a timid exploration of intimacy. Elsa keeps saying the word "bullying", but what she actually means is, "Give me more of your attention, Yvonne!" At this point, the villainess system barely factors into their relationship IMO, since Yvonne is already hooked on Elsa and cannot leave her alone, and her "awakening" to "sadism" is actually more of a realization that she also enjoys interacting with Elsa, slightly confused by the term that both the system and the heroine have stubbornly used for said interactions.