Another welcome 

I just wanted to say welcome and comment on what's happening.

It's unfortunate that your first contributions have led to a discussion which is likely to result in them being undone. The fact that you've switched so quickly to seeking out the relevant discussion pages to find out what the problem is with inserting links to Transfermarkt shows that you' approach editing Wikipedia in a responsible manner. I hope that you aren't put off by Transfermarkt not being regarded as an appropriate source or external link. Actually, in all but exceptional cases, all wikis including Wikipedia itself are not regarded as WP:Reliable Sources.