Photoshop Filter or Action ?

I have no idea if this will work as every single time I try to run it, it crashes my computer and forces a restart, but it looks fascinating and I'd love someone to try it out for me.

1.  You'll need your MX of Nations image and the image you want to edit both open in Photoshop.
2.  Open Neural Filters and turn on Style Transfer
3.  Click on the Image Styles tab and Custom
4.  I never get passed this point but you'll see the source and target images listed under Custom and you'll need to select them.  I imagine there is an OK button to click after this, and if your system does not self destruct, you just might get somethinmg that works for you.  Please be sure to paste before and after images here.

The easiest way would be to use a plugin.  I used a Topaz Simplify > Cartoon effect below.

Starting with this image I took of local rider Steve Lainge

Select Subject and Select & Mask to remove the background

Topaz Simplify to flatten the colours giving it a cartoon effect

Layer Style > Outer Glow to give it the dark fringe

The flag wall background used a Hue/Saturation layer to make it black & White because the same adjustment layer also let me brighten the image taking the blacks out of it.

Hi, could you explain exactly what you have and what you want to achieve, where you are stuck?
The image you showed is an illustration, I think, that's been printed on a t-shirt.

The contrast of the images , made me think that it's been entirely drawn, unless it is the printing process, with some simplification of the colors that gives this impression. There's some slight posterization, some patterns/noise in some shades...
Are you trying to achieve a similar aspect from a photo?

Do you want those particular images printed or do you have new images? There are lots of places on the web to have photos printed on shirts.

... Does anyone have an idea how to do it ?

By @alexanderk2796478

Maybe someone has an idea, but you have to tell us what you actually want to do with the pictures.