I've included both the NZ and Brazilian prices converted to NZD so you can see what you'll be saving.
If you don't know how to purchase games from overseas I've done a tutorial here - https://www.cheapies.nz/node/25561 it's pretty easy.
Remember that you'll be paying a little bit more for the games from Brazil depending on where you get your gift card codes from, currently $200brl = $55.28nzd and CDkeys has $200brl for $56.39nzd.
Brazilian prices converted to NZD are in ()
Mafia Trilogy $82.46 ($51.76)
Spyro Reignited Trilogy $27.98 ($17.40)
Assassin's Creed Valhalla $76.93 ($46.39)
NBA 2K21 $54.97 ($34.51)
Borderlands 3 $36.28 ($22.78)
Watchdogs Legion $65.94 ($38.65)
Assassin's Creed Origins $21.99 ($10.99)
Immortals Fenyx Rising $65.97 ($51.62)
F1 2020 $51.20 ($35.89)
Dirt 5 $71.68 ($50.25)
PGA Tour 2K21 $73.66 ($34.51)
Walking Dead The Final Season $19.47 ($8.56)
Borderlands 3 Season Pass 1 $47.97 ($25.35) Special price ends 22nd Dec
Borderlands 3 Season Pass 2 $48.95 ($27.59) Standard price
Assassin's Creed Valhalla Season Pass $63.40 ($41.41) Standard price
I only listed a small selection of games and DLC so if what you're looking for isn't here go to https://xbox-store-checker.com/en/ and search to see what the price is in the Brazil store, just take note that there's no NZD option so change the currency to Australian to get an idea of the prices.
Here's a link to the sale on the Brazilian Microsoft Store https://www.microsoft.com/pt-br/store/deals/games/xbox I find it easier to search for the game I want on Xbox Store Checker and use their link to take me directly to the page on the Brazil store.
Brazil gift cards from CDkeys ($50, $100, $200)
Brazil gift cards from MTCgame ($15, $20, $25, $40, $50, $60, $70, $100, $200)