Does using Sprite sheet make Construct 2 more efficient ?

Do I have to use Sprite Sheet [A single image containing tons of animations of the player] to make Construct 2 more efficient ?

Or it is just as fine for me to import the character animations frame by frame into Construct 2.

Is one faster then the other during actual game play ?

Or it has no difference, construct 2 will combine all the images together anyway if sprite sheet is really way faster.

Or it really does make no performance difference at all spritesheet or individual.

As far as i know, it doesn't care, C2 will make his own spritesheet when you compile.

Check the manual for the optimisations performed at export time. It does include a stage to process the sprites into spritesheets