Reference

Unreal Engine setup

1. Importing the files (any UE 5.x)

Drop the exported .fbx files into the Content Browser. The files are already in Unreal's axis system and in centimetres, so the defaults mostly work. The settings that matter are listed in CONVENTIONS.md ("Manual Unreal import settings").

Recommended folder layout: /Game/<Project>/Props/SM_*, /Game/<Project>/Characters/<Name>/SKM_* | SKEL_* | PHYS_*, /Game/<Project>/Characters/<Name>/Animations/A_*. The destination_path of each item in the .morenn.json manifest records where MorennBridge expects the asset.

2. Push to Unreal: UE 5.8 project settings for remote execution

Plugins: enable Python Editor Script Plugin (it is loaded anyway by Niagara / RigVM) and Editor Scripting Utilities. Restart the editor.
Edit → Project Settings → Plugins → Python:
- Enable Remote Execution: on
- Multicast Group Endpoint: 239.0.0.1:6766
- Multicast Bind Address: 0.0.0.0 on macOS/Linux (127.0.0.1 sometimes does not receive multicast there); 127.0.0.1 is fine on Windows
- Multicast TTL: 0 (same machine only)
Equivalent Config/DefaultEngine.ini block:
```
[/Script/PythonScriptPlugin.PythonScriptPluginSettings]
bRemoteExecution=True
RemoteExecutionMulticastGroupEndpoint=239.0.0.1:6766
RemoteExecutionMulticastBindAddress=0.0.0.0
RemoteExecutionMulticastTtl=0
```
Firewall: allow the editor to accept local connections (the bridge only uses loopback traffic).
Interchange: Project Settings → Interchange → FBX translator: Force Front X Axis off (the bridge verifies it).
Blender: Preferences → System → Allow Online Access must be enabled, otherwise the add-on refuses to open sockets.
In Blender's Unreal Link panel click Find Unreal; the project name appears in the list. Export with Push to Unreal after export enabled, or push the last export manually.

3. Legacy FBX importer (optional)

UE 5.8 imports FBX through Interchange. To use the legacy importer instead, add to DefaultEngine.ini:

[ConsoleVariables]
Interchange.FeatureFlags.Import.FBX=0

and set UE importer = Legacy in the MorennBridge preferences (LOD groups are then written as real FBX LodGroup nodes, several meshes per file are not supported, generated collision meshes go to separate files).

4. Troubleshooting

Extra Armature root bone: the file was exported without the post-pass (or with Strip armature null node off) from a Blender armature not named Armature. Re-export with the option on.
Bones scaled ×100 / tiny character: the scene was not in centimetres and the file was exported with another tool. MorennBridge always writes centimetres; run Set Up Scene for Unreal.
"No smoothing group information": exported with smoothing = Normals only; use Smoothing groups.
Animation not found / skeleton incompatible: pick the Skeleton of the matching SKM_ asset; bone names must be identical (run Validate and fix E010 on the Blender side).