To my rather astonishment I just read this in a german Thai magazine (der Farang of 3/1/20) that described a visit to such an island close by to Hanoi. Title"Nacktes Inselglück (nude island luck). Just off Long-Bien bridge, the long iron train bridge over the river. Many just name it banana island. Men only, as VN ladies are far too shy to even think of this possibilty to go around. Not gay as such though, but it says its permissive. More or less tolerated as such by the police. Thts not even possible in Thailand.