Basics - How to import a Mixamo character in UE5

The following are basic and generic instructions to correctly import a character from the Mixamo website into an Unreal Engine 5 project. Playing with the options in Mixamo and Unreal Engine 5, more advanced workflows are possible.

select a Character in the Mixamo website.
ensure no animation is selected. If an animation is selected, press the X icon near the animation name
with the character previewed in T-pose, press the Download button
in the Download Settings dialog, set:
- Format to FBX Binary;
- Pose to T-pose.
press the Download button and download the FBX file;
import in Unreal Engine 5 the downloaded FBX file (you can drag & drop the file in the Content Browser, or use the Add > Import to option);
in the FBX Import Options dialog:
- use the Default settings, if in doubt press the Reset To Default button;
- enable the options Import Mesh and Skeletal Mesh;
- set the Skeleton option to None (IMPORTANT - this we'll create a dedicated skeleton matching the size of the imported skeletal mesh);
press the Import or Import All button.

Done :) You'll find the Mixamo character, with its textures and material, in the Content Browser.

Now you are ready to process it with the UE5 Mixamo Animation Retargeting plugin, or maybe you want to import some Mixamo animations before.

Troubleshooting

Wrong bones

The plugin can operate exclusively on skeletons following the Mixamo specifications. The plugin checks the bones names and their hierarchy before enabling the Retarget Mixamo Skeleton Asset action, that remains greyed out if they are not matching the expected ones.

The Mixamo skeleton

In some cases, when using the Mixamo Auto-Rigger system, if the skeletal mesh uploaded on Mixamo already has a Skeleton, Mixamo could re-use it. If this happens, it's very possible that the resulting bone names will not matching the expected ones, and the plugin will not detect the skeleton as being from Mixamo.

The solution is to upload to Mixamo the Static Mesh version of your character, removing the Skeleton from the Skeletal Mesh (you can do it directly inside Unreal Engine 5; or if working in Blender, look at the Armature). This will force Mixamo to add the standard skeleton to the uploaded model.

Fuse characters

When importing some Fuse characters, it's possible that the end result could look wrong.

A Fuse character wrongly imported in UE4. Materials must be manually fixed.

This is a known issue when importing Fuse characters into Unreal Engine: its materials are set to "Translucent" while they should be set to "Masked" or "Opaque" (depending if they're using an Opacity texture or not). To fix it, check all the imported materials and:

if the material has an Opacity texture, set the material Blend Mode to "Masked" and connect the Opacity texture to the Opacity Mask pin;
otherwise set the material Blend Mode to "Opaque".

See here for more details: https://windowsforum.com/threads/how-to-get-fuse-characters-working-in-unreal-engine-4-15.227038/#post-691810 .