Peach-bot

Peach Bots were Peach robots made by Cackletta in Mario & Luigi: Superstar Saga. Cackletta made this robots and put Peach's voice in them. However, when the Beanstar heard the voice it went mad.

It was later revealed that the Peach Bots actually had a Birdo's voice.

Trivia
There was also a Robot Princess created by Kooky Von Koopa that appeared in The Adventures of Super Mario Bros. 3 episode "Reign Storm" when Princess Toadstool was on vacation. King Koopa nearly used it to take over the Mushroom Kingdom.