No release date, platform or region has been announced yet. Source: Official announcement
The anime Frieren: Beyond Journey's End, which first aired in September 2023, marks its third anniversary with a commemorative visual by the studio Madhouse. It shows the current party of Frieren, Fern and Stark celebrating, with Frieren holding the ridiculously huge hamburger steak from Stark's birthday in season 1 episode 12, 'A Real Hero'.
Reflected in the window are Himmel, Heiter, Eisen and Frieren, the party she once travelled with, so that the present and past parties overlap for a moment. The Golden Land arc of season 3 is now one year away.
Announced by the official Frieren anime website
Official source: frieren-anime.jp