At present, Chiayi has a ferry, but you can also consider taking a plane. There are flights in Taipei, Taichung and other places, and the speed is much faster.
If you want to travel from Taichung to Penghu, of course you should fly from Taichung Airport to Penghu Magong Airport. . It is not recommended to take a boat, the plane is fast and efficient, and if it is going against the sea, the wind and waves will be very strong. If you are in Chiayi, you can only take a boat.