Shapeshifter's Quest was created in 2005.
Bruce Coville's Shapeshifters was created in 1999.
Werewolves are shapeshifters
weightlifters
There are several shapeshifters in X-Men, but perhaps the best known is Mystique.
Yes. Shapeshifters are polymorphic because they can change into any form they want to.
In-Quest was created in 1994.
It depends on the lore or mythology you're referring to. In many stories, shapeshifters are not immortal but have the ability to change their form. However, there are also versions where shapeshifters can live longer lives or have a form of immortality.
Dallas Quest was created in 1984.
The Eternal Quest was created in 2003.
Grapplers Quest was created in 1997.
Flimbo's Quest was created in 1990.
Crystal Quest was created in 1987.