The Wikipedia article describes them as "super-elite", and they may have been based on a similar German Army formation, but I'm not sure. What was their role in the military - were they supposed to train other units, and how? Was it unusual that they were involved in front-line combat?
The "Training Brigade" was one of eight divisions totalling 80,000 men trained by German advisors in China to more or less German standards, although these divisions were not fully equipped. This was undertaken because the activities of the German army in Germany were strictly limited by the Treaty of Versailles after World War I. So German military officers went abroad to Russia, China, Spain and elsewhere to practice their craft. China received General Alexander von Falkenhausen who succeeded General Hans von Seekt in China.
These eight elite divisions put up most of the Chinese resistance at the battle of Shanghai, but were too few and too poorly equipped to turn the tide of battle. In theory, the training brigade was supposed to train more Chinese troops, but Hitler pulled Falkenhausen out of China after the war with Japan began. And the brigade was too immediately needed (for defense of major cities) to continue its training role.
Later in the war, the US followed a similar concept by creating the American trained and armed X Force based out of India with about 75,000 men.