Question about ASUS Rog Strix Z370-E Gaming

If you mean the i9 9900K, yes, but it needs a BIOS update. With luck, it's already installed at the factory. Otherwise you have a problem, I'll quote myself from another discussion: "Flashing without a CPU is only possible with the high-end boards. If you're lucky, the right BIOS is already on it. I think digitec somehow also offers a service where they flash the BIOS for you. You might have to write to support."

In general, however, I would advise a Z390 board, just because of the power supply.