Tyler McVicker (VNN) - Valve are "deep in Half-Life development", two Half-Life games are potentially in the works

Tyler claims there is simply too much data to cover in one video, and will release information episodically every two weeks.

Although possible, It's unlikely we'll see anything HLX related for HL2's 20th anniversary, though Valve are seemingly planning a celebration for it.
Reaffirms that HLX is a flatscreen Half-Life game.
Addresses rumour of a game in development for Valve's Deckard VR headset. Potential VR sequel to Half-Life Alyx that has some sort of asymmetrical multiplayer component connected to HLX.
Assets are being labelled with Half-Life themed icons in game files.

Sounds interesting. Guess we'll have to wait and see.