How to stop textures from getting blurry?

Hello everyone!

I'm making a 2d isometric game and for that I'm using sprite sheets for the characters. But every time i try to apply it to a cube/plane i get a blurry texture.

These are the images/settings I'm using:

(these are the results, what i get from unity in the left side and what i want in the right side)

(t$$anonymous$$s is the sprite sheet I'm using)

(these are the material settings)

(these are the image settings)

Important!

I know that t$$anonymous$$s was answered before and that people say that to fix t$$anonymous$$s my textures must have a size of power of 2, but in some cases that's not very good for performance or for the pixel image itself, so is there any good way of doing t$$anonymous$$s? (a way of fixing the blurriness and not cause any other problem later)

Thanks in advance!