No. McClellan was longer, a more fundamentally sound boxer and a great left hook to the body. Granted, his peak was very short because he declined quickly (even before the tragedy), but at his best he was two full levels above Charlo. (And I think Charlo is good.)
Probably not. McClellan was a massive weightbully for his weightclass, certainly at 160, with a huge punch and totally insane reach. His issue was that he didn't seem to carry that power late and could be outboxed by even mediocre fighters at the time, so getting past 6 rounds almost guaranteed a win for a quality opponent if the hole initial onslaught put them in wasn't too deep. But, I don't think Charlo is good and durable enough at 160 to get past the 6th, so no deal for him.
addon: Can you imagine someone that rehydrated an estimated 22 to 25lbs before stepping into the ring, with modern day prior day weigh-ins? Nobody sane would expect he did that in any legit fashion, but still. He would probably come in close to the cruiser limit if he had that much time to dehydrate.
He did much more hitting than he did getting hit, and it's not like Charlo is some master boxer. If you can take Julian Jackson's best shots, then you can stand up to anything Charlo has to offer. I do agree that he was a massive MW whose size advantage would have dissipated at 168 and beyond, and that he was vulnerable to world class boxers. I'd favor all of Jones, Hopkins and Toney over him for that reason. But I don't regard Charlo as being in that category, and this is at 160.