Send to Unreal breaking bone scale

Development Character & Animation
1

Hello, Unreal friends!
I have started to learn Unreal recently. I come from Blender + Unity, and I have got some issues with Blender export.
I first used a classic Blender to FBX to Unreal workflow, but scale was messed up, and I got problems when applying cloth simulation.
I then discovered SendToUnreal, and started to try it out. I managed to fix the cloth error, but then I saw that animation had break entirely.
My model is rigged with Rigify, with a default scale in meters of 1. Scale have been applied (picture1) . In the addon settings, “Automatically scale bones” is marked.
If I export to Unreal, a warning saying “Imported bone transform is different from original” shows.
The scale of the model is fine, and the cloth simulation is correct. Size seems in good parameter. (picture 2)

However, if I then go to the animation tab, bone size is completely broken, and the animation is pure noise (picture 3)

If I deactivate the “Automatically scale bones” in the Blender addon, the problem gets reversed: animation looks perfectly fine, but cloth size is too big and collision is not working again (picture 4)

If then I try to reduce the scene scale in Blender to 0.01, as someone suggested, the imported animation looks fine, even with the “Automatically scale bones” option checked… but the model looks tiny and unusable in Unreal!

That was the issue that convinced me to move away from pure FBX exportation, and use the oficial addon. At first, I thought it was a Rigify issue, but looking closer, seems like the same issue than before.
I expected the oficial addon to get rid of this issue. Is indeed a bug, or there’s something I am not doing right here?

2

Resurrecting this thread to bring more awareness to this.

This is still an issue.

Automatically Scale Bones explodes animations.
Leaving it disabled will make it seem correct in some ways, but will inherit the common Blender to UE bone scaling issues.

It’s quite frustrating because doing manual scaling in Blender yields inconsistent results, and is not a practical solution when working on larger scale productions.

A lot of the tutorials and documentation out there are outdated and combining that with the changes between UE4 to UE5, features or buttons that used to be solutions are either gone or changed, and it’s back to square one.

This add-on really has the potential to bridge the gap between Blender and Unreal, but in its current state just seems to be making that gap larger.

3

It really never did. Epic, as always, refused to listen to any feedback from all the ones who had created Blender to Unreal plugins in the past.
The end result has always been a gigantic mess.

Aside from trying a number of other plugins including my own…

There’s an unreal plugin file that lets you import the blend. Which is what Epic should have gone and done from the start.
Give that a shot.

4

I have the exact same issue with broken animations due to bone scaling, everything the same as Carcasanchez described, except that I don’t need cloth simulation, just the skeletal mesh animations.

5

There is this solution to armature size, but It didn’t work for my Rigify rig, changing root scale and applying it as a rest pose ruins it.

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