Yes, the game will stay in your account, it’s not another free weekend. With regular updates and new modes still arriving even 2 years after release, For Honor is still going strong, or atleast Ubisoft is trying to get more warriors on the field. And the game is genuinely good, absolutely pick it up if you haven’t yet. The game was previously free on Epic Games Store earlier this month, and also with PlayStation Plus this year. Even the Starter Edition went out free for a limited time on Steam last year. Ubi is clearly trying to get the game the attention it deserves, honestly.
Grab the game here: https://register.ubisoft.com/forhonor/en-GB
For Honor is up for grab until 27 August, 1:30 PM IST, make sure to add it to your account by then. The game was released in February 2017 on PlayStation 4, Xbox One and PC.