Here's the PC Games preview video (in German language), who were allowed to release this video after playing at Microsoft's HQ. It gives further insight on the AoE: Definitive Edition gameplay and looks for the Hittites and Egyptians, as well as the grouping feature, the new age advancement bar and gathering points.
A note to everyone here: Please refrain from posting any leaked video's, we will remove them immidiately - you could face a ban if you keep posting leaks.