Nelson believes everybody at the Emirates will be surprised by how much he has grown, emotionally and physically, during his time away.
He said: “People will be shocked, 100 per cent.
“Now I have a more mature role about me. I look to play link-up play, one v ones, and I think I am so much more mature."
Nelson made 23 Bundesliga appearances, 18 off the bench, and scored seven times.
He said: “I not only developed as a player in Germany but also as a person.
“There were times when I wasn't starting and I didn't have a lot of people to talk to, just my family. It made me grow up as a person and on the pitch it showed.
“Whenever I got minutes, I'd have to take any opportunity that came my way.
“I learned so much stuff at Hoffenheim and made a lot of friends. I also made good connections with the managers. They taught me a lot that I can take on in my career.
“It was a very social club and the players used to go out together a lot. They presented me with a video and gave me a Nelson signed framed shirt as well. It was really nice."