At your height, it might be OK, but because it is kind of a chunky little bag with 3" depth, it will stick out a bit. I'm 5' 6" and it just looks silly on me crossbody so I only wear it on the shoulder.
I agree with ithers too that it really depends on the body type of a person and what strap lenght the square mini has. I noticed that new Caviar Chevron mini only has a strap lenght of 19.5 inches and Im 5'2 not that skinny and when I ordered it I mainly wanted it to be a crossbody bag but when I tried it it looked so awkward so I have to give it up and sell it since I got it from a personal shopper. Some square minis have 20.5 strap lenght so those might work on skinnier ladies😊
When I tried square mini in the store, the strap length just a bit too short for crossbody.. I decided to buy it as I really love this chevron caviar combo, rare!! . I told myself that's ok I just use it as shoulder or double chain as handheld bag. In the end, whenever I use my square mini, I still prefer to wear it crossbody, so much easier and comfortable when walking. I just try to shift square mini slightly to the side to make the chain length looks longer.. lol
I am 5'3, my modeling pics below for reference.
Strap length of my mini square is 20.5 inches.