With the cancellation of E3, studios and publishers are making their announcements on their own, at their own pace and as they go. Baldur's Gate 3 is no exception, as Larian Studios announced they'll show more of the game on June 6.
Given the teaser, we can expect the presentation of new classes and environments, but many are waiting for the moment is the opening of early access on Steam, which could happen this summer.
UPDATE: The event has been postponed from June 13 to 15 as a sign of solidarity for the Black Lives Matter cause.