Yes, SWEETSOP is a Scrabble word!

Letter values in Scrabble US: S 1, W 4, E 1, E 1, T 1, S 1, O 1, P 3.

Is it a valid word?

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

tropical American tree bearing sweet pulpy fruit with thick scaly rind and shiny black seeds
sweet pulpy tropical fruit with thick scaly rind and shiny black seeds

Also: sweetsop tree, annona squamosa, sugar apple.

Not playable in Scrabble US: ANNON.