The following amiibo unlock costumes for Mario
Source: http://www.monamiibo.com/super-mario-odyssey-amiibo-guide/
Mario (SSB/SMB/Super Mario Maker)
Gold/Silver Mario
Luigi (SSB/SMB)
Dr. Mario (SSB)
Wario (SSB/SMB)
Waluigi (SMB)
Diddy Kong (SSB/SMB)
Wedding Mario
Wedding Peach
Wedding Bowser
NOTE: Any other Peach or Bowser amiibo will not give you costumes.
Source: http://www.monamiibo.com/super-mario-odyssey-amiibo-guide/
Mario (SSB/SMB/Super Mario Maker)
Gold/Silver Mario
Luigi (SSB/SMB)
Dr. Mario (SSB)
Wario (SSB/SMB)
Waluigi (SMB)
Diddy Kong (SSB/SMB)
Wedding Mario
Wedding Peach
Wedding Bowser
NOTE: Any other Peach or Bowser amiibo will not give you costumes.