You can get sponsors on kits for the PS2 versions of WE7 and PES3 and this will be happening very soon. It was easily done for WE6:FE and you can see examples of the kits in the Editing section.
To have these sponsored kits, you need to use a kit patch. First you download a patch, then you apply it to the image of the game either WE7 or PES3 (the patches are game-specific and won't work on the other game), then you burn a new copy of the patched version of the image. This patched version will only run on a chipped or modded PS2. Info on these mods can be seen in the Editing section as well as more info on patching and the kits.
You cannot use X-Port to apply sponsored kits, only patches.