If Russia had some sort of involvement with the US election ten it definitely would have some sort on affect on the outcome. Whether or not trump will be the next president would depend on how involved Russia really was. There is also the chance of influencing American people by Obama's order.
If the review is made in time and the results are enforceable than it could reverse the earlier decision that Trump was the winner of the race. However just finding out that Russia did interfere in the elections n might not be enough to prevent Trump from being sworn in.
Before the election, the liberals thought that Clinton was going to win. They scoffed at the idea that Russia would be able to influence the election or cheat the vote. Now that Trump won the election, they are grasping at straws. Russia has not produced any evidence that they were involved in the election.
No, Obama's order to have a full review of Russia's possible involvement in the U.S. election will not have an impact on the outcome of Trump being elected. Donald Trump has won the election, and the final step in having him assume the presidency is for the electoral college to vote. Republican electors will not select a Democratic president.