Well, Asus is one of the largest and oldest hi-tech manufacturers in the world, with worldwide distribution of products ranging from displays, laptops and optical drives to server components, graphic cards and motherboards. They have dozens of motherboards in current production, supporting likely 100s of older boards with documentation and technical info. They have offices in at least 20 Asian countries and 30-40 additional countries worldwide.
Emaxx appears to be a small Phillipine motherboard company that sells or sold 20 models.
Very hard to compare the companies. I don't even know if Emaxx makes their own products. Comparing the motherboards made by these two companies is quite difficult - for all I know, Asus makes the MBs that Emaxx sells.