Don't be ridiculous! If Trump was a sleeper agent for Russia he would now be doing all sorts of things to fulfill that role. Like cozying up to Putin, alienating and angering our allies, undermining the USA's influence and prestige throughout the globe, embarking on trade wars to weaken the economy of the USA and our trade partners, undercutting democratic governments in favor of strongman dictators, turning Americans against one another by sowing hatred of fellow citizens, fanning fears and unease in the American population, and attempting to discredit the key democratic foundations of our own society, including the FBI, the State Department, the courts,and the press.
And what would be the point? If Trump were to even begin such treachery the people of the US and the Congress, including those in his own Party, would rise up and kick him out of office within a week. Come on, we are talking about obvious treason! We are not some 3rd world country where a greedy and corrupt wealthy strongman could take power and blatantly seek personal gain at the cost of the welfare of the population, the future of the country, and the ideals that make us a society!