what is the nearest route from jiang nan subway station to yue an mansion building, guangzhou?

It is about 0.9 miles between these two places. You can choose to take a bus or reach on foot.
Get out of the Exit E and walk about 160 yards to Nancun Station to take the bus No.44 to Qianjin Road. Then walk another 170 yards, you will reach the mansion.

The walking route is like this: Take the Exit C and walk eastwards along East Jiangnan Road for 350 yards, and then turn left to walk northwards for 450 yards to Qianjin Road. Turn left and walk about 90 yards, you will find the mansion.