Blizzard seems to be shifting their monetisation model with the arrival of Overwatch 2 as the new one will have battle passes, which leaked alongside some other features.
Battle pass system was brought to prominence by Fortnite and it has been used by just about every live service game in existence today. Overwatch was one of the exceptions to the rule but this will no longer be the case when Overwatch 2 launches, it seems.
With just a few days before the Overwatch 2 beta kicks off, it appears that an .exe file has been leaked, which led to numerous discoveries by data miners.
Chief among them is the mention of the battle pass system which is all but confirmed at this point. It remains to be seen how this will affect the loot box progression that is currently active in Overwatch - whether it will be removed, altered or untouched.
The last on the list is highly unlikely as the company will probably want to get as many people to purchase the battle pass as possible, meaning that randomly getting its rewards from a box at each level up may not be very profitable. Alternatively, it's possible that battle pass rewards will be unique to the reward tracks so the loot boxes will remain more or less the same.
Besides the battle pass, there is a mention of clubs, which is basically your clan or guild system seen in many games before. Creating a sense of community could certainly help Overwatch 2 in retaining the players, especially if they keep grouping up for PvE content and progression of the more challenging encounters.