Just look at N31 and then guess what N32 will look like. It is pretty damn obvious.
Draw a line that cuts the right most 2 MCDs off and there you have 3 SEs with 16CUs each, an oversized command front end + the display engine on the left and a little bit of additional space. That would mean increasing the CU count per SE to 20CUs would fit easily and boom you have N32 in a 200mm^2 package with 4 MCDs which we know means 256bit bus.
That is what will power 7800XT.
A cut version with 3 MCDs (192bit) will be what powers the 7700XT.
Performance I don't really know. I can take a guess at 7700XT because I think it will be 48CUs and the uplift vs 6750XT will be similar or better than that of 7900XTX over 6950XT which would put in in 6800XT territory. 25% more shaders, 33% more bandwidth and IC on the 7800XT and maybe higher clocks due to more power and a better bin would put the 7800XT in 4070Ti territory which is mighty close to the 7900XT but if N32 does not need to draw such stupid amounts of power to hit high clocks like N31 does then maybe that is just what will happen. Analysis suggests that a $700 7800XT would be higher margin than the $900 7900XT or the $1,000 7900XTX so AMD may not mind it being that close in performance given the margin is better, especially since $900 for the 7900XT is overpriced anyway.