You do not need boots for the Camino Portuguese.
It is a long walk, not a mountain hike.
Unless you have really weak ankles or unless you are a boot person who has a pair of VERY well broken in boots, stick to trainers.
Goretex does not work for me. 6 to 8 hours of walking causes my feet to sweat and goretex holds in the moisture, causing blisters.
I'm not arguing with anyone, just saying that is MY experience.
Your feet do not get as wet as you may imagine and if they DO get wet, trainers will dry overnight easily.
Just wear a good trainer with some nice tread and you'll be fine.