Are lawyers in Porto really that affordable? That is enticing. I'd love to talk this through just to have a non-actionable idea about the legality of this situation.
It's not the legality or the right to work from home that is in question. You too live in a small country with too much corrupt politicians and networks of influence.
If I named the company I would be uniquely identified by my immediate superiors as soon as they read this. I might as well ask you if you have any job for me in a couple of months. I really like Porto.
I wouldn't worry too much. For all the bad things our country has, labour court isn't one of them (well it can be) as it almost sides with workers all the time. If they try to fire you, they will end up paying you a lot and give you your contract back.
I believe it will eventually be known, and I hope someone starts some kind of campaign to boycott companies who are doing things like this during this crisis.