The “bra” looks like the top part of a more fitted version of images from the Wenceslaus Bible of the late 14th century. Their distinctive dress appears to consist of a spaghetti strapped or strapless, semi-fitted underdress, between knee- and ankle-length.
The braies look like 15th Century men style, but with strings on the side instead of fabric band. As seen from the model Italian “Calzon”, 15th century.
"Is there any evidence to support the idea that the "brief" is in fact a woman’s garment? Just finding it with some "bras" does not make it a piece of feminine clothing. My underpants are frequently "found" with my wife’s bras……" from the discussion on Armour Archive.