Hello! It depends of context, ok? But ill try to explain it. "Washed up" is used to refer something that you were so good in the past, but now you are not anymore. For example:
"Julio was so good like a soccer player 10 years ago, but now he's all washed up"
Washed up = used too much and cant use it no more
It's something like this. Did u catch? [emoji] I hope so! If not, check it out on URBAN DICTIONARY
Cheers!