This is mostly for summoner duels and I want to build a vantage centred team so who screams vantage sweeper like no one else
Dual phase brave weapon users like Altina, Lex and Laslow if you activate his weapon refine.
Otherwise I would say units with high atk with fury or push so they enter into vantage range with ease and also use brazen seals that increase atk.
As premiummix said, dual phase brave users.
Other non-brave users are units with massive one-shot potential, such as Tikian.
other options are characters who can do things like launch powerful specials
Characters like Ares or Bridal Nailah are quite good at this (shameless plug)
Vantage sliding off meta abit due to units getting more bulky over the years and nowadays you tend to either kill or die in one battle more often so kinda hard to be in vantage range. Plus summoner battles can be won by stall teams so you might hit or miss.
If that’s your plan I submit a long term goal of:
Dance + Vantage + dual effective damage + B!Marth A Slot (since it has recoil) + Special Spiral B slot and 2 CD special.
Max investment (10 merges + 15 flowers +Atk IV) = 61 Atk. Pretty damn good for a support unit!
Yen’fay might be a good vantage user as well… having DC and DR built into his prf is quite nifty
He would much rather have NFU
Literally my first thought after I wrote my post^^