Best team for ORAS and how to obtain them?

Ingame? Literally any pokemon that can hit neutral on everything. Alone

Just use your bros anon. Ingame doesn't matter

>>33359782
Exp Share lets you use anything you want if you turn it on, but generally Mudkip blitzing the game is your best bet. Pick up the primals for easier mode as well.

>>33359782
Starter
Zigzagoon
Wurmple
Poochyena
Fossil
Event Shiny Beldum this one is the most important.

Depends on what you mean by best team. Competitively there is no such thing as a best team. Ingame there are some mons that make a playthrough considerably easier but is extremely easy already. A good ingame team that i can suggest is:

Blaziken : Imo best starter, sweeps through the game on itself until you get to the flying gym.

Gardevoir: Strong overall, Kirlia even gets Magic Leaf to counter water types that Blaziken has trouble with. Also early route mon.

Milotic: Ridiculously easy to get in the remakes and really powerful.

Lati@s: Probably kind of gamebreaking. I never used it myself ingame though.

Mega-Absol: Easy to get and sweeps through gym 7 and Phoebe all by itself.

Primal Kyogre/Groudon: Roflstomp every opponent you encounter through the whole game. If you want/need it that easy here you go.