We kinda knew it was happening, but now it's confirmed: Apex Legends crossplay is coming -- confirmed during EA Play 2020. Respawn also announced "Lost Treasures Collection" which is the new seasonal event for Apex Legends, check it out:
The new Lost Treasures Collection seasonal event changes Apex Legends up a bit, with core design modifications in the new limited-time game mode "Armed and Dangerous Evolved". This allows players to use a resurrection tool to pick up knocked-out teammates, as well as some wicked twists on players' abilities.
As for crossplay, Respawn and EA announced Apex Legends would have crossplay across all platforms -- this means that someone using EA Origin's launcher or Steam (yes, Apex is coming to Steam) can play together with their friends across the PC, Xbox One, PlayStation 4, and even the Nintendo Switch.