There are certainly things you can do, but this may not necessarily be one of them. It’s depends on the route and how you’d align freedom with the UDHR. For some examples:
In elections, the UN would have had to have been asked to observe, for them to then be able to be involved. This is to maintain the sovereign judicial control of the nations at hand. if they were invited to observe, they can also be asked to hear and judge.
If Trump is a risk to the rest of the world or another member state. Then the security council would be involved. The problem is the USA has a veto as a permanent member. So he’d likely just demand someone veto it.
If he committed or incited a mass genocide, he can be called up in from of the International Criminal Court and tried there. However, it would have to be proven beyond all reasonable doubt and it would have to be lots and lots of people. has to be tens of thousands if not more.
WTO or trade with other bodies. Some foreign countries may be able to help here. The EU in particular will insist on alignment with human rights legislation before trade. That’s the world’s largest trading bloc. The problem is that Trump doesn’t care.
Either way, sounds like a great idea!