Iirc only the RED signs with Capture Point on them are square (overlays not props). I dont remember if they were one-way as well, but 2 way is possible.
Well that comes from the styles of both teams. RED has always been covering their secret bases with rather natural stuff, while BLU is industrial - hence these differences and some others in assets.
If you are unable to think of a way to adapt your idea to fit the existing signs then you will have to make your own.
It should be very easy to recolour the blue square signs to be red.
I am NOT going to tell you how to do it. However I will provide all the links you need for information on how to learn yourself, or else you will run into this problem again and people will lose patience to explain to you every step.
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