New wheel combination – now unbalance 90-130 KM/h

Hello, how ready described above short and scarce: Exchange from the original BMW 19 inch winter wheels on brand new Vossen replica 20 inch rims with ET35, along with brand new Nexen Nfera SU1 with the prescribed size including H&R DR (screw plates) 30mm track plates on all 4 wheels. Have had everything installed during tire service. Now the following problem: Vibrate and shake the steering wheel and under the car between approx. 90-130 km/h. Can this come by wrong force? on the one side of the support surface have a wrong centering? (according to the report, there is only one side in it, which is 72,5mm, so the side where the rim is located should be correct as far as possible) Can this be due to the Nexen tires (rather than premium tires) or that these are simply so “bad” from the quality that you have to live with it!? (always Hankook Ventus Evo had on it, after recommendation I wanted to try the Nexen now because they are also a ticking cheaper.) Driving behaviour on the highway or country road is pretty annoying to me. Can someone help me here and possibly have an idea that I don’t come up with? And again: Before the exchange, so with the winter bikes on original 19inch BMW Alus everything was fine, not the smallest vibration or the like. I thank you …