Games like Eternally
Games like Eternally include Gloomhaven, Jagged Alliance 3, King Arthur: Knight's Tale, Stolen Realm, and The Last Spell. We matched them by the tags players give Eternally on Steam (Tactical RPG, Turn-Based Tactics, Hex Grid, Online Co-Op, and Dark Fantasy): closest matches first, and among equally close ones the better-known games.

Gloomhaven
Shared: Online Co-Op · Tactical RPG · Dark Fantasy

Jagged Alliance 3
Shared: Turn-Based Tactics · Tactical RPG · Turn-Based Strategy

King Arthur: Knight's Tale
Shared: Tactical RPG · Turn-Based Tactics · Dark Fantasy

Stolen Realm
Shared: Turn-Based Tactics · Tactical RPG · Turn-Based Strategy

The Last Spell
Shared: Turn-Based Tactics · Turn-Based Strategy · Tactical RPG

Demeo
Shared: Turn-Based Tactics · Tactical RPG · Turn-Based Strategy

TROUBLESHOOTER: Abandoned Children
Shared: Tactical RPG · Turn-Based Tactics · Turn-Based Strategy

Wargroove
Shared: Turn-Based Tactics · Tactical RPG · Turn-Based Strategy

Wartales
Shared: Turn-Based Strategy · Tactical RPG · Party-Based RPG

Marvels Midnight Suns Digital Edition
Shared: Turn-Based Tactics · Tactical RPG · Turn-Based Strategy

For The King
Shared: Online Co-Op · RPG · Co-op

Fell Seal: Arbiter's Mark
Shared: Turn-Based Tactics · Tactical RPG · Turn-Based Strategy

FINAL FANTASY TACTICS - The Ivalice Chronicles
Shared: Turn-Based Tactics · Tactical RPG · Turn-Based Strategy

Legends of Kingdom Rush
Shared: Turn-Based Tactics · Tactical RPG · Turn-Based Strategy

For The King II
Shared: Turn-Based Strategy · Online Co-Op · Party-Based RPG

Age of Wonders 4
Shared: Turn-Based Strategy · Dark Fantasy · Tactical RPG

Songs of Conquest
Shared: Turn-Based Tactics · Turn-Based Strategy · Strategy RPG

Forsworn
Shared: Turn-Based Tactics · Tactical RPG · Turn-Based Strategy

Frosthaven
Shared: Tactical RPG · Turn-Based Tactics · Dark Fantasy

King Arthur: Legion IX
Shared: Tactical RPG · Turn-Based Tactics · Dark Fantasy

Warhammer 40,000: Rogue Trader
Shared: Tactical RPG · Turn-Based Strategy · RPG

Warhammer 40,000: Chaos Gate - Daemonhunters
Shared: Turn-Based Tactics · Turn-Based Strategy · Strategy RPG

Tactics Ogre: Reborn
Shared: Tactical RPG · Turn-Based Tactics · Strategy RPG

King's Bounty II
Shared: Tactical RPG · Turn-Based Strategy · Hex Grid