So the reason it’s taking so long is that your mesh has 200,000 triangles. This doesn’t really seem to be a game-ready model and will take much less time after getting that poly count down.
It works for us with binary and if you’d like to export successfully, you’ll need to use binary. I added some simple animations to your base mesh that you sent me and imported it successfully using the export settings I’ve sent you.
The only other thing I can suggest is that you attempt using 4.9 and see if this issue persists.
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