Hi! If you were to show us the other ninjas you currently have, it might be easier to suggest teams. Without that info, as general suggestions, Killer Bee [Seven Swords Style] and Earth Main would be good supports.

Catacly is right, if you wanna build a team that is somewhat meta-relevant, you have better ninjas than Roshi you c*e. His suggestion is a team that I think was meta a while back but I don't know how well it'd do now against the big meta threats of BT Kushina, Kakuzu, and Edo Minato. Roshi doesn't have the greatest attribute tags (only his Jinchuuriki status is helpful out of them) unlike the meta ninjas mentioned above, who have tags like Secret Jutsu (Kushina) Edo Tensei, Sage Mode (Edo Minato), and Akatsuki (Kakuzu) that mean there are a lot of support ninjas for their category.

The Roshi suggestions the others gave are good, but I'll just throw in another option.

This doesn't have reliable healing like catacly's team suggestion, but it has buffs and a bunch of shields. Roshi gets buffed by Bee and Earth Main (you could also use the pose of Duel passive, but I think Earth Enhancement is more reliable here since it's not situaitonal) and Gakido supports the whole team w/ debuff clearance (even though Bee and Roshi are immune, this could help if you face Kushina who removes immunity with her mystery).

And...just as a bonus, here's another team you could run with the ninjas you have that might be more competitive:

You have both Nagato and Gakido at 4 stars so maybe you have their breakthroughs, which would make this even better. Even if you dont have them, the most important ones you'd want here are +2 on his last passive (Sealing Jutsu Absorbtion) and Y+2 on his first chase/passive (Rinnegan: Dominance). That way he will support Ay, himself, and Gakido.

I gave you two options above but I can go into more detail about the non-Roshi team, as I personally think it's the most solid team you can make at this point.

The whole team revolves around Nagato, even though he isn't the pos 1 ninja (his mystery is strong, but in its non-breakthrough from it's not a prompt mystery which makes it less viable). His abilities allow him to support other Edo Tensei ninja (in this case, Ay [3rd]) by removing their debuffs and making himself immune. If you use Gakido and have Nagato's Y+1 Rinnegan passive, he will also make Gakido and himself immune if they have shields and also makes it so that his own mystery can't be dodged when he has the shield. Earth main is important for keeping these shields up. If you have Nagato's +2 Sealing Jutsu Absorbtion passive, this will get easier, since it will give himself and Ay a shield each turn as well. These breakthroughs are just bonuses though, you don't need them immediately to use this team.

Ay [3rd] is the pos 1 ninja because he's the strongest Edo Tensei ninja you have. He's nice in that he as super armor but can break super armor on others with his mystery, so you have a chance of countering meta super armor ninjas like BT Kakuzu and Rinnesharingan Sasuke. He also scales, which is an important skill and something pretty much all top tier meta ninja do. "Scaling" means a ninja can get more powerful on their own outside of being buffed by someone else, due to certain conditions like being hit (Kushina, Roshi), triggering their chase (Edo Minato), or having a certain amount of chakra (Kakuzu, RinneSasuke, Ay). Ay will increase his Ninjutsu and Defense the more chakra you have, so this is part of the reason you want to run the Deep Forest Wall mystery on Earth main, because it will generate extra chakra for you in round 1. Ay's biggest problem is that he isn't immune to debuffs, but Nagato mostly solves that problem.

For your fourth ninja, there are a bunch of options actually. Gakido might be the best since he's supported by Nagato, can provide additional debuff clearing and also a shield, but what he lacks is the ability give the team extra chakra or power buffs. Ay really needs the chakra for his scaling but his and Nagato's mysteries use quite a lot, too. So, here are some other options.

You c*e either version of Samui actually, regular or swimsuit. Regular samui doesn't heal or give any attack buffs but she will give herself and Ay extra shields at the start of the battle, and she gets chakra. Swimsuit samui gives a 30% additional attack increase and will remove one debuff from herself and Ay each round. She also makes a shield with her mystery, but you'd probably want to use it on Nagato not Ay since it also makes the target immune to chases and Ay already is. It's up to you.

Mabui is another option who falls between the two Samui forms. She heals, gives chakra, and shields herself and Ay at the beginning of the fight but her mystery isn't that useful. If you use a different version of this team and find you're always lacking chakra, try this out.

I don't have all of these ninjas so I can't use these teams, but if I did I think it might be fun. Hopefully this helps, sorry it's a lot of explanation but I like making teams and explaining them. Good luck!