Create a design for a classic button-up shirt split vertically down the middle. The left side of the shirt is themed after Mythra from Xenoblade Chronicles 2, using her white, gold, and green color scheme and design elements. The right side of the shirt is themed after Shadow the Hedgehog from the Sonic the Hedgehog series, using black and red colors and design elements inspired by him. The shirt should look like a stylish, wearable piece of clothing with a clean split down the center.