Yeah buying shoes online is iffy. Especially heels bc they can really pinch you in all sorts of ways. Also for heels and sandals, the sizing is what it is - you can’t cheat with thinner or thicker socks.😅

In the case of open toe, open heel shoes, I agree with your coworker that there’s a chance they might fit. I’m a US 6 and have gotten away with 5.5 heels before, pretty much bc of the fact that there are no socks involved. My foot heel came right up to the edge of the shoe (I don’t love this look but oh well lol). If you really love the shoes and want to take the chance, I’d just buy the 10.5 and return it if it doesn’t fit.

Also if they hurt to wear, don’t bother. These heels were not made for you. It’s not worth it!! (Kinda sorta yelling at my younger self lol😆)

As long as you can return I’d say give it a go, you’ve got wiggle room cos of the sandal design.

Simple: No, don’t do it! But there is one point: half a size is the variation between different brands anyway. -> Just compare the (real measured) shoe length and how wide it is at the forefoot.