https://wccftech.com/borderlands-3-sold-an-estimated-two-million-copies-on-epic-games-store/

We knew Borderlands 3 sold very well on PC (where it is only available on the Epic Games store, at least until April), as 2K described the performance as the highest-selling for the label in the initial five-day window. Even Gearbox CEO Randy Pitchford boasted about the concurrent players when compared to previous Borderlands games on PC.

We never got an exact sales figure, though. Now, website PlayTracker has attempted to narrow down an estimate of that by cross-referencing the nine most popular games on the Epic Games store as they were recently revealed by Epic with data grabbed from the Xbox API (on PC).