Hyper Beam Mewtwo for PVP?

No, I can't think of a worse option for PvP. 1 bar, easy to dodge and not SE against anything.

Edit: It's also resisted by Mewtwo best counters, ttar and Gengar.

Hyper Beam did receive a buff with the great gen2 change to charge moves, but it would need a much bigger buff to make it really desirable on Mewtwo or Dragonite. That being said, if you have a lot of Mewtwos, then you could keep one with Hyper Beam, for all I care, in case it does get a buff.

The only reason I can think of to save a HB Mewtwo are:

1) It's a novelty move that probably won't ever come back. If you have more Mewtwos than you know what to do with, sure, keep one with HB.

2) If you're in a PokeDraft league, it's nice to have a Mewtwo with Normal, Ghost, Psychic, and Fighting attacks, so when you take your one into a raid, you can pick the attack that is optimized. Partly Cloudy weather makes HB pretty good.

The article that GamePress posted today argues that SB and FB cover all the possibilities that HB could cover, but better, between the two of them.

At this point thinking about PvP is just gambling. If you reason with counters, your opponent will as well, so Niantic will need to find a way to prevent battles turning into a boring chain of each player switching out its pokemon for one that counters the opponent's one more heavily. That could mean locking pokemon switches, which could mean neutral damage and pokemon with attacks of 2 different types would be more useful, because they would have better coverage. But again this is gambling, pure speculation.

If you can afford, keep one with HB. But don't count too much on it being useful.

To mitigate, this is coming from someone who is salty for having burnt all his CTMs to try to get SB to his 2nd and last Mewtwo. Ended up with FB. Should have kept HB and saved my last 2 CTMs.