You can go from Porto to Vigo and then with a slow intercity through northern Spain to Irun/Hendaye, very scenic and recommended. Probably need to stay the nigh

You can go from Porto to Vigo and then with a slow intercity through northern Spain to Irun/Hendaye, very scenic and recommended. Probably need to stay the night in Vigo as those trains go only once or twice per day. I'm not sure why the article says you can take a normal train from Coimbra to Hendaye, there is only a night train, though it does have seats (not recommended, take at least a couchette or bed). Currently suspended due to corona afaik.