Obstruction maybe but that is tricky to prove. Since there was no collusion then why would Trump fire Comey when he was investigating Trump and Russian collusion? There might be another unknown reason for obstruction but its hard to prove.
Well, there is obviously things trump didn’t want to get out that would turned up by an investigation. Like the hush money payouts to the two ladies and any other issues some of his staff had. So I can see why he would want to obstruct, but like you said, hard to prove and really impossible to prosecute since he is the sitting president...