Yes, it is, but it is not simple as "copy Nadal from this patch to this other patch", because players' features are separate. I mean, they are not a single whole thing, they are a compound of things (shirts, shoes, animations etc.). So, what you would need to do to copy Nadal (just an example) is copying the shirt texture he uses, the shorts, the socks, the racquet, the animations, the grunt, his face (most importantly) etc., and put this altogether in your new patch. If you want to copy his stats too, you would need to take it from Players.ATP.ini from the old patch and put it in the new patch.
In summary, you would have to edit a lot of things. I suggest looking how to add a shirt first. After that, adding shorts and other outfit parts is similar. Then move on to animations and then stats. Once you understand it, you will be able to replicate it for other players. But it will give you a lot of work