Create shirt with text for animated character (8 simple designs)

I have an animated character in 2 different png files. I need him to wear a simple t-shirt in both. I need 1 black version and 1 white version with both and 4 text slogans for each (8 shirts in total)2 x black shirts with white text slogan for image 12 x white shirts with black text slogan for image 1
2 x black shirts with white text slogan for image 2
2 x white shirts with black text slogan for image 2

Will lead to more work