HI Poly Rig with mixamo

Hi Guys,

I have a high Polygon Model and I would like to rig it with mixamo.
The model is 500 MB as a obj.
If I bind itin Cinema with a bone chain nothing happens. The model stay in T Position
When I use the autoriger, mixamo gives me an error.

Is it important to reduce the polygons to a max of 100.000 Polys or less.

Is there a workflow anywhere?

Thanks

Max