I actually hear it as a bracing, masculine name - it has a masculine origin & meaning. We’re also already comfortable with boys’ names ending in -a or an -uh or soft “er” sound (Micah, [name_m]Ezra[/name_m], [name_m]Asa[/name_m], Jasper), and I don’t think those endings automatically read as feminine or make people worry about feminine associations. (And then there’s everything we’ve already said about feminine qualities not being a bad thing - and even being good/ making for a balanced and functional person!).
That said, I can understand why (Mc)Kenna sitting so close to names like [name_f]Jenna[/name_f] and [name_f]Anna[/name_f], might be perceived as”girl” by a number of people. And while I’d like to think I’m not especially influenced by gender norms, I clearly am and it’s popping up in this way: part of me would only want to use the name on a boy who’s likely to grow into a sturdy, winsome-looking man; someone who could plausibly be in On Campus (
). I suspect the gendered assumptions might be harder to carry if McKenna were lean, highly introverted, and nervy.
There’s also the question of cultural context. To me, McKenna feels like it could work esp well in the (US) [name_m]South[/name_m] (or where its naming styles are predominant).
Overall, I like the name and think you should keep on your list!