UE 5.5 Steam Multiplayer: OSS Steam vs Advanced Sessions vs SteamCore?

I’m developing a Steam-only 5v5 FPS in UE5 and planning to use a host migration plugin.

I’m trying to decide between:

  • UE 5.5 + OSS Steam

  • UE 5.5 + SteamCore

  • UE 5.4 + Advanced Sessions

My priorities are:

  • Stability and reliability

  • Steam invites and overlay

  • Steam Cloud

  • Future support for Steam Inventory / microtransactions

  • Compatibility with a host migration system

I’ve seen reports of Advanced Sessions issues in UE 5.5, but I’m not sure how serious they are. For developers currently shipping Steam multiplayer games:

  1. Is OSS Steam stable in UE 5.5?

  2. Would you recommend OSS Steam, SteamCore, or Advanced Sessions for a new Steam-only project in 2026?

  3. If you’ve implemented host migration, which setup worked best for you?

Thanks in advance!