Trump's exec order can only involve the exec branch or declare a national day of prayer - that sort of thing. I think it will be more along the lines of ordering the DOJ to investigate whether they are too big and should be split up, such as IBM and Ma Bell was sued by the government on the last day of LBJ's term and the suit was active into the 80s - or investigate the possibility they are public utilities subject to regulation (despite the law suit - things change) - or perhaps order the FEC to investigate election tampering...or all of them. I think that is where it is headed.
Trump just can't order them not to censor - it doesn't work that way. He is not a dictator and the law certainly doesn't support him in that effort.
I believe the fact that Twitter and Facebook are both publicly traded on the stock market makes a case for them behaving in a manner consistent with public needs where Constitutional Rights are concerned, specifically 'freedom of speech' and the CENSORSHIP thereof.
Good argument, see you in court! lol BTW, do you think the U.S. Military should still control the Internet?