Werner is not good at all against defensive teams. I've watched a ton of Leipzig games and everytime teams sit back deep, he's almost invisible. That's why he's also had it very hard in the German N11 so far.
He's good when he has a ton of space to make his runs and use his great speed, but outside of that he's really average at best in most other areas (first touch, technique, finishing, vision, decision making etc.), which really limits him a lot in those kind of games.
The one thing I was really disappointed with was Lampard's use of Havertz. I'm not the biggest Havertz fan either, but I still recognize him as a great talent. Playing him so out of position those first two matches didn't do him any favor.
For the bright spots: I thought their defensive plan and execution (outside of that one red card) has been really good so far.