Yes, FREELANCER is a Scrabble word!

Letter values in Scrabble US: F 4, R 1, E 1, E 1, L 1, A 1, N 1, C 3, E 1, R 1.

Is it a valid word?

FREELANCER is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

a writer or artist who sells services to different employers without a long-term contract with any of them

Also: free-lance, free lance, self-employed person, self-employed.