What would be the result of using chicken livers when making liverwurst?
Let me do a breakdown of the typical ingredients of liverwurst ("Leberwurst") roughly based on food laws in Germany (aka liverwurst country):


roughly 10% - 30% (sometimes up to 40%) liver:
mostly pork because it's cheapest, using partly veal or poultry is more expensive but tastewise no big difference.
muscle meat and bacon, again typically pork, but beef, veal and poultry is also used either alone or as add-in. 
usually a generous amount of spices.


The liver is influencing taste and texture, but the used regular meat and especially the spices play a big role, too. Using a "too dominant" liver or too much in total can be overwhelming, but there's no accounting for taste. While pork, veal and poultry livers are comparatively "mild" and can be used interchangeably (or as you said, the results will be in your +/- 10% range), beef liver has a tendency to make the liverwurst bitter, so it's use is not recommended.