First of all, let me congratulate you on finding a flirtation opportunity in quarantine!
That's a feat.
Of course, I don't know her and can't come to any definitive conclusions about whether she's flirting with you or not. But if I boil it down, it looks like our questions are -- can you/how would you share your feelings, and is it okay to start a long-distance-relationship when you're physically separated. In short, my answers are, yes feelings! Yes to LDRs! But I will try to put something more helpful together
The only way to know whether these feelings are reciprocal is to be honest with this person about your *own* feelings, so I tend to be team "tell her." Just make sure that you're sharing your feelings without setting expectations for her response! That can be hard if things don't happen the way that you think they will. As for how to do it, we are always down to help you make a pro/con list or work through ideas that you have!
And as for starting an LDR -- it's not uncommon for folks to begin LDRs when they are already stationed in different home bases. I think you have an advantage, too, because you've spent time together in person before and have a good sense for who each other are 1-on-1. Anything that makes you both feel good is "okay!"