I had to replace the rear motor mount on my other car, a Toyota Matrix, because of an exhaust leak. The flanges wouldn't line up enough for the spherical gasket to work. This car has a different joint and engine mounting, but one of the flanges might have bent.

 

Just a guess but it is possible you stressed the collector joints in the manifold and cause them to crack - or opened up an existing crack.

How far down did you lower the rear of the transmission to install the mount?

Did you leave the midpipe bracket connected when you dropped the transmission rear?

You need to try and locate where the loudest noise is to determine the exact location of the leak - if you cracked the manifold you get a free catalytic converter for that price...

 

There is a support in transmission when they changed tha mount.

Also the when you compare the new and old mount. The old mount is already squish

 

This is the old and new. It seems the new mount is much higher. IVe check the oem mount online it seems not much higher

 

The main issue is the new mount whichi is for outback. We replaced it with old mount and the issue is gone.. the rockauto make a mistake in listing

 

I don’t think it a Rock Auto issue. You have a 2017 XV model which outside of the US and Canada is the same as a 2018 in the USA. Rock Auto lists parts for the USA market so you have to take that into account when ordering.