Update: A spokesperson from Sega confirmed that players will have a way to transfer progress from Xbox One and Windows 10 to Steam. "You will be able to link your account. We will release a guide on the official website soon. PSO2 will be cross-play and cross-progress with Steam, Xbox One, and Windows 10," said Sega in a statement.
Back in May, Phantasy Star Online 2 finally launched in the West on Xbox One and Windows 10. Microsoft had helped bring the free-to-play MMO to the Western market. That meant that while PSO 2 was PC, PS4, and Switch in Japan, it was only coming to Xbox One and Windows 10 in the West. Despite that, Xbox boss Phil Spencer confirmed that the game would "end up on all platforms" eventually.
Just prior to PSO 2's Western launch, documentation pointed to a potential release on Steam as well. Sega didn't mention anything about a potential Steam launch, focusing on releasing the game on Microsoft's platforms first.
Today, a listing for Phantasy Star Online 2 appeared on the Steam store, with a planned release date of August 5, 2020. The Steam release will come alongside the launch of Episode 4, the next content update for the Western client. Sega is also promising full cross-platform play on PC and Xbox One. We've asked Sega if there will be a way to transfer progress from the Xbox One and Windows 10 version to the Steam client and will update this story when we receive comment.
"It is our goal to bring Phantasy Star Online 2 to as many players as we can," said Fred White, PSO 2 Team North America's Head of Marketing. "We have heard the requests for a Steam launch, and we are excited to announce that soon Steam users in 36 countries on six continents will be able to experience PSO2 on their platform of choice, including popular features like Steam Achievements and Remote Play."
Sega recently announced Phantasy Star Online 2 New Genesis, an update and overhaul for the existing game. New Genesis offers vastly improved graphics, a changed combat system, and more robust character creation options. It'll live alongside the classic PSO 2 client, which won't be going away, and players can choose to play on either version of PSO 2.
Though it was announced for Xbox One and Windows 10, it's likely that New Genesis will be coming to Steam as well. The announcement page was very specific, stating: "If PSO2 is added to new platforms, we plan to make PSO2: NGS available on those platforms as well." That's great, because playing the PSO 2 beta really hammered home the need for a sequel, and New Genesis seems to fit that bill.