Games like Returner 77
Games like Returner 77 include Outer Wilds, Observation, GRIS, The Turing Test, and Deliver Us The Moon. We matched them by the tags players give Returner 77 on Steam (Adventure, Indie, Puzzle, Space, and Female Protagonist): closest matches first, and among equally close ones the better-known games.

Outer Wilds
Shared: Space · Adventure · Puzzle

Observation
Shared: Adventure · Indie · Space

GRIS
Shared: Indie · Adventure · Female Protagonist

The Turing Test
Shared: Puzzle · Adventure · Space

Deliver Us The Moon
Shared: Adventure · Indie · Space

Contrast
Shared: Indie · Adventure · Female Protagonist

COCOON
Shared: Adventure · Puzzle · Indie

Chants of Sennaar
Shared: Adventure · Puzzle · Indie

Neva
Shared: Adventure · Indie · Puzzle

There Is No Game: Wrong Dimension
Shared: Indie · Puzzle · Adventure

Call of the Sea
Shared: Adventure · Puzzle · Indie

Chorus
Shared: Adventure · Indie · Space

Carto
Shared: Indie · Puzzle · Adventure

Iris.Fall
Shared: Adventure · Puzzle · Indie

Q.U.B.E. 2
Shared: Adventure · Indie · Puzzle

The Last Campfire
Shared: Adventure · Puzzle · Indie

Rise of the Tomb Raider™
Shared: Adventure · Female Protagonist · Puzzle

Never Alone (Kisima Ingitchuna)
Shared: Indie · Adventure · Female Protagonist

J.U.L.I.A.: Among the Stars
Shared: Adventure · Indie · Female Protagonist

Detention
Shared: Indie · Puzzle · Adventure

Tomb Raider Game of the Year
Shared: Adventure · Female Protagonist · Puzzle

LIMBO
Shared: Indie · Puzzle · Adventure

DreadOut
Shared: Indie · Adventure · Female Protagonist

Samsara Room
Shared: Indie · Adventure · Puzzle