To be fair in OOT Link is practically wearing a mini skirt. So I don't really see that as an issue. For the shoulder strap you don't necessarily have to replace the fabric but I would definitely suggest using a real buckle even if it doesn't function. If you want to replace it but don't want to use real leather a smooth vinyl would work really well or even a strap made of the same material your boots and gloves are made of. You would probably want to pad it a bit so it sits above you rather than on you. His gloves have bunches so you could consider folding some loose horizontal pleats on your gloves then securing them with a few blind stitches. It should add that layered effect.
"I see now that the circumstances of one's birth are irrelevant; it is what you do with the gift of life that determines who you are."