Well, seeing how in Reigen's profile it shows that he likely has more abilities due to having all of Mob's 100% abilities, Reigen wins due to: Mind Manipulation, Power Mimicry (Just cancel out his Finger Bullets with his own, or even copy his Muscle Transformation), and Attack Reflection.
However without Mob's abilities, the only thing Reigen has against Toguro is force field creation, which I see Toguro easily breaking through. Toguro wins here due to Reigen's lack of abilities to counter in this situation.
I will see what other people think before putting out my thoughts. My answer also depends on if Reigen is allowed to use Mob's abilities or not.
Also: This is my first actual answer so please go easy on me.. lol.
Reigen could rag-doll from afar via heavily outranging all of his abilities and having far higher lift strength with his telekinesis. Though he seems to not immmediately go for that so that's definitely a problem for him. Toguro could do soemthing with his soul-hax but if it just pulls souls towards him then Reigen could probably just break out of the pull.
Depending on their AP, Reigen could beat him up before his poweres run out or Toguro could outlast. So I'll probably go for inconclusive unless someone can bring up their actual statistics.
Reigen scales to 100% Mob creating the giant broccoli from Toichiro's explosion, which is 408 kilotons. If I'm not mistaken, Toguro should scale to Hiei's mastered Dark Dragon, which was in the 500 kiloton range, so Toguro has the AP advantage.
Given that Espers in Mob Psycho seem to be immune to any kind of soulhax that evil spirits have, I doubt Toguro's soulhax would be any different.
Toguro in character doesn't start with hax usually and starts with physical attacks or with finger bullet which is basically his only long range attack and his soul hax was reault of Toguro transforming into 100% which required weaker demons souls in order to transform though he doesn't demomstrate soul hax normally
Reigen is a conman whose powers in this situation are a temporary transfer from Mob. However, he may be a bit of a coward, but he's more than willing to go all-out the moment he realizes his opponent is a threat.
So, I guess that means in character Reigen gets serious a lot quicker than Toguro.