Well i fail here, i used the same subnet of the vmbr0 thats why it didnt work... ofc its can work if a subnet is already used but there is another problem to in ordner to use this vlan dhcp i needed to restart the hole system cause after refreshing the network everything dont work anymore, no internet<- So after setting it up and after proxmox refresh the network it didnt work so i have restart the system and then it did work why it is like that idk but if i change something i need to restart. Now it works Thanks!
i was hoping to use it on my main subnetwork but sadly that wont work. So i gona only use importen vm on my main subnetwork and set it up manuel and for others just that new vlan0 of the SDN /Vnets
Thanks