To get Sonic Mania running on your console, you won't be looking for a single .iso or .wbfs file. Instead, you need the following:
Depending on your Wii system settings and cables. GameCube Controller Support: For that authentic retro feel. A Quick Warning on ROM Links sonic mania wii rom link
Your console must be able to run custom apps via the Homebrew Channel. To get Sonic Mania running on your console,
You need the specific Sonic Mania Wii port binaries (available on GitHub under the RSDKv5-Decompilation project). A Quick Warning on ROM Links Your console
Talented homebrew developers have taken the original game engine and decompiled it, allowing it to run on hardware it was never intended for. Thanks to these efforts, you can actually play Sonic Mania on a softmodded Wii with impressive performance. How to Play Sonic Mania on Wii