Foreign born athletes who might represent Germany in Rio:
Athletics:
Aleixo Platini Menga (born in Angola, mens 4 x 100 m)
Peter Emelieze (born in Nigeria, mens 4 x 100 m)
Homiyu Tesfaye (born in Ethiopia, mens 1500 m)
Fate Tola (born in Ethiopia, womens marathon)
Sosthene Moguenara (born in Tchad, womens long jump)
Alexandra Wester (born in Gambia, womens long jump)
Marie-Laurence Jungfleisch (born in France, womens high jump)
Lisa Ryzih (born in Russia, womens pole vault)
Lilli Schwarzkopf (born in Kyrgyzstan, womens heptathlon)
Boxing:
David Graf (born in Armenia, mens -91kg)
Artem Harutyunyan (born in Armenia, mens -64kg)
Arajik Marutjan (born in Armenia, mens -69kg)
Track cycling:
Kristina Vogel (born in Kyrgyzstan, womens keirin/sprint/team sprint)
Equestrian:
Meredith Michaels-Beerbaum (born in USA, jumping)
Fencing:
Matyas Szabo (born in Romania, mens sabre)
Field hockey:
Kristina Hillmann (born in Switzerland, womens hockey) (I dont know if she always had the german citizenship)
Football:
Mahmoud Dahoud (born in Syria, mens football)
Kathrin Hendrich (born in Belgium, womens football)
Dzsenifer Maroszan (born in Hungary, womens football)
Rhythmic gymnastics:
Jana Berezko-Marggrander (born in Russia, individual)
Anastasija Khmelnytska (born in Czech Republic, group)
Handball:
Evgeni Pevnov (born in Russia, mens handball)
Judo:
Martyna Trajdos (born in Poland, womens -63kg)
Table tennis:
Dimitrij Ovtcharov (born in Ukraine, mens table tennis)
Han Ying (born in China, womens table tennis)
Shan Xiaona (born in China, womens table tennis)
Weightlifting:
Almir Velagic (born in Bosnia, mens +105kg)
Graf, Harutyunyan, Vogel, Szabo, Berezko-Marggrander, Ovtcharov, Ying and Velagic are already qualified.
Maybe i forgot someone, i didnt check all athletes in rowing and rhythmic gymnastics ...
Overall 20 different nationalities.