I had a seat-mate in college whose cologne was so strong. You really don’t need to see her in a place before you know she’s in that area, her cologne was so unique-unique in a very bad way. The smell of cologne was terrible and strong at the same time. She was my seat mate, I was subjected to that torture for a very long time until I decided to do something about it. No, I didn’t go to meet her straight to tell her about her cologne-when it was her birthday, I simply gifted her a cologne with mild smell. I had peace when she started using it. She liked it too, she told me when she started using it (girl, I already know, you don’t need to say it). I told her I love it too and that she should simply stick to using it, I helped write down the store I got it from so she could get more. That was how I handled the situation without making it awkward. You could also try this method if you wish.