Hiruzen animated was recently released in China about 2 or 3 months ago. We have a ways to go. Probably 1 or 2 years before we even see him. Minato is a strong ninja and is extremely strong if you can protect him and keep him alive as he scales over the course of the fight.

Really depends on your playstyle. Masked Obito wont give you a ton of damage output. Mostly a cc ninja. He does have one of the strongest chases in the game though since it does ignore resistances and defense, then immobilizes. If Roshi is currently your go to ninja, then I wouldn't recommend using them in the same team due to Obito's Tailed Beast passive.

Minato on the other hand will give you damage output. He also interrupts two ninjas as well. Comboing c*e his mystery almost every round. Only thing is he needs to stay alive at least 3 or 4 rounds to truly shine.

Its a hard call since they provide different things pvp wise. Its almost like comparing Rosh and Han...you know? Both relatively strong but one is more utility and the other gets better over the course of the fight.