Take Metro Line 3 and transfer to Metro Line 4. According to the search on Baidu Map, from Nanjing Station to Huadong Hotel, you need to take Metro Line 3 and transfer to Metro Line 4, which takes 30 minutes in full. Specific bus routes:

1. Take Metro Line 3 from Nanjing Station and go through 2 stops to Jimingsi Station.

2. Arrive at Jimingsi Station, walk about 90 meters, transfer to Metro Line 4, take Metro Line 4, and go through 3 stops.

3. Arrive at Nanyi·Second Division·Caochangmen Station and walk about 870 meters to Huadong Hotel.