25 cards where it’s legal in Brawl and the card types include “dwarf” and the colors is R

Glóin, Dwarf Emissary (The Lord of the Rings: Tales of Middle-earth #132)
Magda, Brazen Outlaw (Kaldheim #142)
Magda, the Hoardmaster (Outlaws of Thunder Junction #133)
Torbran, Thane of Red Fell (Throne of Eldraine #147)
Ambergris, Citadel Agent (Alchemy Horizons: Baldur's Gate #12)
Axgard Artisan (March of the Machine #332)
Electrostatic Infantry (Dominaria United #122)
Fearless Liberator (Kaldheim #135)
Fearless Skald (March of the Machine #138)
Gimli, Counter of Kills (The Lord of the Rings: Tales of Middle-earth #129)
Storm-Kiln Artist (Outlaws of Thunder Junction Commander #181)
Axgard Cavalry (Kaldheim #121)
Brazen Dwarf (Adventures in the Forgotten Realms #134)
Breakneck Berserker (Kaldheim #124)
Dwarven Forge-Chanter (The Brothers' War #131)
Erebor Flamesmith (The Lord of the Rings: Tales of Middle-earth #122)
Hangar Scrounger (March of the Machine #142)
Minecart Daredevil // Ride the Rails (Wilds of Eldraine #141)
Pillardrop Warden (Strixhaven: School of Mages #112)
Plundering Barbarian (Adventures in the Forgotten Realms #158)
Rimrock Knight // Boulder Rush (Throne of Eldraine #137)
Seven Dwarves (Throne of Eldraine #141)
Skewer Slinger (Wilds of Eldraine #149)
Twinscroll Shaman (Strixhaven: School of Mages #118)
Vault Robber (Kaldheim #158)

Though this query has ended, its relics still slumber in New Argive.