There is not any confirmed news about it yet. on 2007 valve releases 2 part of half life, its sequel has to be completed but yet it is not. On the second portal of 2011 half life universe dormant next version for 10 years which is a shame for its developers because this game is considered to be the best games.
Cut to the Chase
It is the long waited and quite far absent part of game series named as Half Life Saga. You cant play it soon because there is nothing announced about it yet.
Expected Plot Summary
In 2017 the composer of Half Life announced a short tale named as Epistle 3 on his personal blog. Composer mentioned to the post as fanfic. Its fine clears that post is plot summary of game, Half Life 2: Episode 3 will be with some names changed and the genders would be reversed. If you are willing to read its complete tale with names and genders changed, you can have that on Git Hub, there someone has composed complete short tale of it.
Leaked Concept Art
The writer Valve has just rarely spoken about this game. We have a fine bit of its idea art hit the net over the past decade. It will not be similar to games renders and trailers. It just provides us some hints that how it will be, we can just expect and hope about it. The nature of game will possibly change in its new version.
Half Life Remains Unconfirmed
Time is passing day by day but the composer Valve is still quiet, and we can expect that he is doing perfecting the game in its every aspect. Games should be developed in a way that they should stay afloat. But we all want Valve to establish it as soon as possible and put our mind at rest that we are hoping waiting for it far long time.