I want to reverse the coordinate origin in Inkscape to top left corner. By default (0,0) stays at bottom left. Changing it to top left corner will help me in designing a sprite sheet for my game.
You can't. There's an ongoing change to address this an additional work on making it user-configurably. https://bugs.launchpad.net/inkscape/+bug/170049
It's targetted to the 0.49 release so perhaps if you try a "nightly" it'll have what you're after?
In Inkscape 1.0 the coordinate system is reversed, so that the top left corner is (0, 0) by default.
You can download the beta version from the official site, or install it with snap:
snap install inkscape --edge