
On a Billboard seen in Whistlestop Rails is an advertisement for Yo'ster Cookies Flowers, paying tribute to the game Yoshi's Cookie.

A can of "Starbeans Iced Coffee" can be spotted in the flip-side version of the stage "Poochy's Magma Run". This is a reference to the Starbeans Cafe found in Mario & Luigi: Superstar Saga.
In an interview with Nintendo Everything, the game's director, Masahiro Yamamoto, confirmed that the game takes place in a Kindergarten class within the Mario universe.