Its hard to choose but I have a lot of merch of Isabelle from Animal Crossing so I'll go with her. <3
Can't list any specific one, but Lemmy and Boo Diddleys are probably the closest things I've got to true favorites from Nintendo games overall. But my love for Noiverns is probably greater.~
Marx is a good world-dominating boy. Who wouldn't want to rule Popstar? Waddle Dee also never did anything wrong.
Probably Yoshi. Actually there are a bunch of characters from the Mario franchise that I love. Iggy, Bowser, Dino Pirahna, the Boos, Luigi, the Lumas, etc. The list goes on. I like King Dedede as well.
Ruby from the adventures manga. One of the few times this story has made a really good and complicated character that has a compelling character arch to support him. By far one of my favorite character Nintendo has produced. I realize this isn't video game related so here's my next favorite character, Shulk because I love the progression of his character.
A'ight. Lets see here... Ghiriam (i know i spelt that wrong), Magolor, Marx, Waluigi, Fi, Waluigi again...the list goes on.