No. I practically beat my emerald game (though I didn't beat the elite 4) without almost ever having a grass type Pokemon on my team. You should, however, at least catch grass type Pokemon, as to fill up your Pokedex.
all you need is skill and you need to look in the grass they are always hiding in there
no you can't trade it to emerald lol
To get a Dunsparce in Pokemon Emerald you need to trade for one from Pokemon FireRed or LeafGreen. Dunsparce can be found in Three Isle Port in the only patch of grass that's there.
you can't you need to trade a houndour from diamond or pearl
to make appear missingno in Pokemon emerald you need a advance map and make a grass patch configure to make appear Pokemon but only 2 or 3 and play the modified ROM go to the new grass patch and you will find missingno but if you want catch you need the master ball save before you catch missingno sometimes he disappear of your game
The grass is the best, because in the end, you will need him a lot! It is though only based on preference (But i heard you like Mudkipz)
no just go to him but i am talking about Pokemon emerald
You cannot find an infernape in Pokemon emerald for that Pokemon you need Pokemon platinum, pearl or diamond.
Go to this link for all you need to know and its a great site for all Pokemon info and its not some stupid website its really good http://www.psypokes.com/emerald/legendaries.php
You need to search until finding it then look at the area you can catch it, DO NOT FLY to the closest town WALK TO IT or it will move again.
You need to Migrate it from Pokemon emerald
You don't need to defeat the Pokemon league to find relicanth in emerald version you can find it anytime underwater near Mossdeep city its very rare to find though so you may have to stay in the grass underwater for a long time.