Games like Mortal Online 2
Games like Mortal Online 2 include Black Desert, The Elder Scrolls Online - Standard Edition, Rust, Albion Online, and FINAL FANTASY XIV Online. We matched them by the tags players give Mortal Online 2 on Steam (MMORPG, Sandbox, Open World, Character Customization, and RPG): closest matches first, and among equally close ones the better-known games.

Black Desert
Shared: Sandbox · MMORPG · Exploration

The Elder Scrolls Online - Standard Edition
Shared: MMORPG · Open World · RPG

Rust
Shared: Open World · Sandbox · PvP

Albion Online
Shared: MMORPG · Open World · Sandbox

FINAL FANTASY XIV Online
Shared: MMORPG · Character Customization · RPG

Pax Dei
Shared: MMORPG · Sandbox · Open World

Mount & Blade II: Bannerlord
Shared: Open World · Sandbox · RPG

Gloria Victis: Medieval MMORPG
Shared: MMORPG · Open World · RPG

The Elder Scrolls IV: Oblivion® Game of the Year Edition (2009)
Shared: Open World · RPG · First-Person

Terraria
Shared: Sandbox · Open World · Exploration

Hogwarts Legacy
Shared: Open World · RPG · Character Customization

Trove
Shared: MMORPG · Sandbox · Open World

Dark and Light
Shared: Open World · Sandbox · RPG

Neverwinter
Shared: MMORPG · RPG · Open World

No Man's Sky
Shared: Open World · Exploration · Sandbox

ARK: Survival Ascended
Shared: Open World · Sandbox · Character Customization

The Quinfall
Shared: MMORPG · Open World · Character Customization

Once Human
Shared: Open World · Exploration · Action

Mount & Blade: Warband
Shared: Open World · Sandbox · RPG

The Elder Scrolls IV: Oblivion Remastered
Shared: Open World · RPG · Character Customization

Kenshi
Shared: Sandbox · Open World · RPG

Dragon's Dogma 2
Shared: Open World · RPG · Character Customization

Mortal Online
Shared: Open World · Sandbox · MMORPG

Last Oasis
Shared: Open World · RPG · Sandbox