Can infants eat fish maw (花胶？How old do they need to be to safely eat fish maw? Thanks!

It depends how old is your kid. If below 6 months and has not started on solids then I will refrain from giving. If your kid has started on solids then maybe just a little soup provided it is not too salty, sweet or oily. By one year old then no problem to try a variety of foods. Just a little to taste.