No it won't work with PES4, but I'm currently looking into making a stadium pack for PES4, featuring just the stadia and the new grass textures for the pitches. There are other PES4 patches (Jonboyo's being the most obvious) which give you the kits, and the balls and boots etc., but I don't think there's a patch for PES4 that has all the stadia, and there certainly isn't one with the stadia I made myself. I still play WE8 personally, but I'm going to have a good look at the stadium folders in PES4 and see how easy it is to transfer the files.
You shouldn't all keep talking about a cd-rip torrent, because the mods will box your ears. But there definitely is one about (nothing to do with me), and it's only a matter of time before it turns up on the big torrent sites. I'm only telling you lot cos you've all got the original WE8, of course...