His offensive qualities are impressive for a LB. However, his defending weakness cost him the starting spot.
I was dissapointed from Jansen at the Euro, to be honest. He has always shined for the National Team, I was expecting the same at the Euros. He started well actually, he was quite good in the first match against Poland. But, he screwed everything against Croatia, and lost his spot.
He will get his starting spot back though, I'm very sure of that.
Playing in the CL with Bayern will help him a lot, he will strenghthen in every aspect and get valuable experience. He has a bright future, undoubtely.