I'm not even going to bother with all the ones that are clearly extinct actual animals or ice age remnants, the following are the ones that I think possible even though many might not. If anyone wants me to go into detail let me know, and I won't say 100% positive, but the following is a list:

Sasquatch - big hairy guy recorded throughout history spanning many races and cultures on every continent but Antarctica.

Little People - duende, puckwudgies, etc. Almost as widespread as sasquatch

Ghouls - tall pale humanoid necrophage common in folklore of Middle East, Europe, and North America. See also wendigo.

Faeries - perhaps not the creature itself, but the phenomenon of a "land of the faeries" where people are said to go that vanish into thin air in the woods is a worldwide phenomenon.