It seems that striders only have 1 texture for their legs, which means that both the left and right legs of a strider has the same texture (which the other leg is not mirrored).
Strider leg isn't mirrored
Striders use the same part of the texture for both legs
Piglin and Zombified Piglin right arm/leg/loincloth textures are identical to the left ones
Hoglin and zoglin tusks textures are not separate