Green Lantern 2

Green Lantern 2 is a proposed sequel to Green Lantern which is due to star Ryan Reynolds which was slated to be cancelled.

Why It Was Cancelled

 * 1) Plans for a MCU-style DC Comics universe, as well as this was cancelled while the movie getting flopped at the box office.

Result
The sequel is permanently cancelled. The film was rebooted in 2020 as Green Lantern Corps.