If you haven't changed the equipment tiles @ 1B0000,
or changed the equip screen palette from 1B7040 - 1B707F,
then this is for you.

Items on the equip screen will have a black box & white text if equipped.
They will have a black box & grey text if not equipped.
An orange orb if equipped & not highlighted, & a grey orb if unequipped & not highlighted.

It's just a repalette of the equipment tiles @ 1B0000, using the vanilla equip screen palette.

1B7048 02 for equipped.
1B7068 02 for unequipped.