If this is the law in Sweden it should be immediately repealed, precisely in order to prevent people from arguing that a political donation counts as legally-punishable "damage to a company" if it's the wrong kind of political donation.
The fact that you're claiming that a donation to an anti-immigration political party is the sort of conduct that people "held to a higher standard" by law should be forbidden from doing is a type of political censorship that you're trying to enact via the mechanism of corporate law, and it's worth destroying that mechanism of corporate law over it.
He has clearly brought the company into disrepute. The appalled reaction of so many of their customers is ample evidence of that.
It doesn't really matter how that's happened - it wouldn't be the donation that's the problem from the pov of corporate law in other countries, it's the fact that a company director has harmed the company.
The fact that you're claiming that a donation to an anti-immigration political party is the sort of conduct that people "held to a higher standard" by law should be forbidden from doing is a type of political censorship that you're trying to enact via the mechanism of corporate law, and it's worth destroying that mechanism of corporate law over it.