I have just researched and written in english the coastal route from Porto to Redondela which is incredibly beautiful. You follow the coast so it's nice and flat crossing beaches and dunes before catching the ferry from Caminha to enter the Galician border town and port of A Guarda continuing to follow the coat via Baiona, Oia,Nigran and Vigo until you get to Redondela where it meets the official route. Can't beat it for sheer outstanding beauty and easy on the legs!! Check out a summary of the details here
http://caminoways.com/ways/portuguese-coastal-way-caminho-da-costa Will be uploading a video of the route in the next two weeks. For places to stay I suggest you use my mate Lusi Freixo's Blog with excellent, detailed maps in all formats see
http://www.caminador.es/?page_id=117Buen camino.