As much as I recognize Kirito's ability to pull stuff seemingly out of his ass and win against all expectations, I see no way for Kirito to defend against LLENN while she uses the classic "Run and Gun" strategy.
Firstly, Kirito likely won't be able to simply cut and dodge her bullets, since the P-90 has a faster fire rate and without plot-armor, he won't be able to just tank an entire spray. This means Kirito has to use the enviorment for cover, at least temporarily.
Even if LLENN does manage to miss an entire clip, Kirito likely won't even be able to land a hit on her, even while she's shooting, because she'll almost certainly be running in circles while she shoots (and we've seen her moving accuracy is exceptional due to her build and her weapon). LLENN's movement speed is obviously superior (effectivelly blitzing 4 pros at close range) even in the air (as seen when she jumped over and landed behind the last pro), so she should have no trouble running away while she reloads. This does give Kirito several seconds to either recover or reposition, but I don't see him being able to keep up resistance until she runs out of ammo.
If LLENN does ever end up at close range with Kirito, there's no guarantee he'll land a hit. We know his skill with the sword is really good as he spent multiple years inside SAO, but LLENN's character is very small in size (
https://i.imgur.com/aj8bRlF.png), and as such, I'm of the opinion that landing a hit on her isn't going to be as easy as Kirito usually had it in BoB. She certainly won't be able to match him for more than a few swings, but even a missed hit can turn into LLENN retreating and starting all over from square one.
Let's make one thing clear. Kirito won't be able to use his shitty Five-Seven to do anything other than scare her (which could work, but likely won't make a considerable difference).
At best, the fight is a stalemate where LLENN wastes all her ammo and retreats, while Kirito stays there out of breath.
I'll give it 6-7/10 to LLENN.