Translucent white htv?

if i really, really wanted to do this, i would do the design a light grey, and print to jpss (with inkjet)

contour cut/weed, then press

experiment and if needed bump the opacity down/darken the grey/use different color/etc

i have a pic here on the forum where i did a full color jpss on a black and it came out as a ghost


i'll see if i can find it here or on my drive to give you an idea

found it here

i think with your colors it should be even better than on the black

another option is to do your normal white htv, press normal time/temp, but on your re-press do another full time instead of 10 secs, then hit it again for full time the tee fabric will begin to show through revealing a less opaque vinyl

but you need to experiment and be esp. careful of heat press box on your garment (esp. the red)

You could also try Stahls SuperTek Matte Clear HTV. They have videos on their site showing how you can use it to create a tonal effect with dark fabric.