Perhaps McCartney is gender fluid? (8)
I believe the answer is:
designer
'perhaps mccartney' is the definition.
I can't tell whether this definition defines the answer.
'is gender fluid?' is the wordplay.
'fluid?' is an anagram indicator (I've seen 'fluid' mean this).
'is'+'gender'='isgender'
'isgender' anagrammed gives 'DESIGNER'.
Can you help me to learn more?
(Other definitions for designer that I've seen before include "Person who creates or fashions things such as clothes" , "Resigned to being the creator, of fashion say" , "Originator" , "inventor" , "Architect or couturier, say" .)