Tourist Visa?

We fly into Shanghai 22nd Feb 2019 from the UK and stay overnight before joining a cruise on the 23rd Feb which will travel to Tianjin 26/27th Feb. We also visit Seoul, Jeju Island before arriving in Hong Kong 5th March. We also visit Vietnam before arriving in Singapore where we will depart to travel back to the uk.
Do we need a tourist L or is a 144 hour TWOV ok?