Brawler's Plate is one of those cards players keep asking about. Here is, in plain words, what its official text says, the rulings published by Wizards of the Coast, and the combos players actually run.

Official card text

Equipped creature gets +2/+2 and has trample. (It can deal excess combat damage to the player or planeswalker it's attacking.) Equip (: Attach to target creature you control. Equip only as a sorcery.)

How it works : Brawler's Plate

Original English text — Wizards of the Coast / Scryfall

No additional ruling has been published for this card.

Interactions with other cards

These cards' text mentions Brawler's Plate.

Outfitted Jouster

When Outfitted Jouster enters, conjure a card named Steelclaw Lance and a card named Brawler's Plate onto the battlefield and attach them to Outfitted Jouster. If damage would be dealt to Outfitted Jouster while it's equipped, prevent that damage. When damage is prevented this way, sacrifice an Equipment attached to Outfitted Jouster.