Doom Absolution should have been the sequel to Doom 64 and offer a 4-player mode but the project has eventually been cancelled.
Planned on : Nintendo 64
Publisher : Midway
Not really a sequel to Doom 64 but a deathmatch-oriented game similar to Turok : Rage Wars (which will be released much later). The game has been cancelled in July 1997 after some months of development only to allow the team to focus exclusively on the Nintendo 64 versions of Quake I & II.
Dark Rift is a 3D fighting game released shortly after the console.