There is no official "Super Smash Bros Brawl WAD file" that contains the full game. Nintendo never distributed full Wii games as WAD files through official channels. If you see a file labeled Super Smash Bros Brawl [NTSC].wad that is 4+ GB, it is almost certainly an ISO or WBFS file with a renamed extension.
There is a massive distinction between a standard ISO/WBFS dump and a WAD file: super smash bros brawl wad file
Launches the game from the Wii Menu without opening the Homebrew Channel first. There is no official "Super Smash Bros Brawl
Some users seek out WADs for the original Super Smash Bros. (N64) to play it on their Wii via the Virtual Console. There is a massive distinction between a standard
A small shortcut on the Wii Menu that boots the full game from a USB drive or SD card.
If you genuinely want a Channel WAD for the Wii Menu (not the game, but a forwarder):