Scratch

If you make a sprite that moves from the arrow keys, then duplicate that sprite, then both sprites (the original and the duplicate) will move at the same time when arrow keys are pressed. This is probably not what you want. So try these scripts

Sprite1

when gf clicked
forever
 if <key [up arrow v] pressed?>
  change y by [1]
 end
 if <key [down arrow v] pressed?>
  change y by [-1]
 end
 if <key [left arrow v] pressed?>
  change x by [-1]
 end
 if <key [right arrow v] pressed?>
  change x by [1]
 end

Sprite2

when gf clicked
forever
 if <key [w v] pressed?>
  change y by [1]
 end
 if <key [s v] pressed?>
  change y by [-1]
 end
 if <key [a v] pressed?>
  change x by [-1]
 end
 if <key [d v] pressed?>
  change x by [1]
 end

Make sure you use those if <key [up arrow v] pressed?> blocks instead of the hat blocks. The hat blocks only report one key at a time, and that's probably your problem. This way, it will always work.

I hope that helps 

PS. You can change what is inside the if blocks to change what happens when the keys are pressed 

No worries, it's a pleasure