If he used the alias "Killer Bee" in his previous life, he was already preparing to be reincarnated as a woman. After all, male bees are totally harmless, without a stinger.
Genderbend? Hard skip. I seriously don't understand why they keep doing this. Just make her a woman in the past life and I would be totally fine with it.
It feels like it's just a cope for authors who wants to write a female lead but incapable to do so, so they put on the excuse that she's "male brained."
Man reincarnates into a woman with big personality. Ah yes.
Since he was able to talk to her, I wonder if he'll eventually be able to separate from her body then they'd end up together lol.