Yes, COWAGE is a Scrabble word!

Letter values in Scrabble US: C 3, O 1, W 4, A 1, G 2, E 1.

Is it a valid word?

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

pods of the cowage plant or the stinging hairs covering them; used as a vermifuge when mixed with e.g. honey
the annual woody vine of Asia having long clusters of purplish flowers and densely hairy pods; cultivated in southern United States for green manure and grazing

Also: velvet bean, bengal bean, benghal bean, florida bean, mucuna pruriens utilis, mucuna deeringiana, mucuna aterrima, stizolobium deeringiana.