I don't think it's going to cover anything outside the 6 core alien films. The description very distinctly calls out Alien, Aliens, Alien 3, Alien Resurrection, Prometheus and Alien Covenant. No books, no comics, no games, no RPGs, no AVP. That's the impression the description gives me anyway:
QuoteDescription
The definitive volume on the Xenobiology, terraforming, synthetics, humans, corporations, military, judiciary, culture, science, spacecraft, hardware and weapons of Alien, Aliens, Alien3, Alien: Resurrection, Prometheus, and Alien: Covenant. Structured in 3 traditional encyclopedic volumes – Non-Human, Human, Action on Nature - illustrated throughout with concept art, photography and illustrations, with a historical timeline and alphabetical index. From the Alien to Zeta 2 Reticuli, from the birth of Peter Weyland in 1990 to the USM Auriga's Earthfall in 2381, this is the comprehensive and authoritative official tome on the Alien films.