As my previous answer, that was deleted, up to now there is no DSL/VDSl modem/router supported, because fo problems with the driver and the management of the modem itself that connects to the Internet Provider.
SO, if you just want a name, I suggest you to look at ASUS DSL-AC68U because it supports a lot of OpenWRT features and it's directly maintained by ASUS. In sense that Asus bases its firmware on OpenWRT
Just to know it, FRITZ!Box 7490 has its own operating system that is NOT OpenWRT.