One way to apply the color would be to do sample the color, add a layer filled with the color, and use a layer mask to apply the color only to the shirt. Here's how:
- Select the Object Select Tool (If you can't find it, then go to Edit > Search and enter "Object Select Tool" in the search field at the top of the Discover panel that opens)
- Make a selection around the Shirt. If you have the Options bar open (Window > Options), then you can set the Mode to Lasso. You don't have to make a perfect selection with this tool. Just draw a rough selection around the shirt.
- Select the Eyedropper tool (you can search for it in the Discover panel again if you have trouble finding it)
- Click on the color you want to use on the other shirt
- While the selection is active, go to Layer > New Fill Layer > Solid Color and click OK in the New Layer dialog.
- The Color Picker that opens should use the color that you just sampled for the fill. If it's correct, click OK.
- If the mask needs to be adjusted, click on the layer mask thumbnail in the Layers panel and in the Options bar, click the Select and Mask... button
- Try using the Shift Edge slider to get more or less of the color to show (by changing what the layer mask reveals) and click OK
- The color will be masked to the shape, but it won't blend yet. Change the Blend mode in the Layers panel from Normal to Multiply.