Remember: RUMOR, not fact.
Screenshot of the Tweet from Kelios.
A Pokémon Presents presentation has been rumored to be happening in June, which is the same month as the digital E3. Kelios is a known leaker who accurately predicted that the last Pokémon Presents presentation, held in February, would occur that month.
This presentation is reportedly going to reveal the release dates for Pokémon Unite, as well as the Diamond and Pearl remakes.
[Additional Sources: Nintendo Life]