Using a shortsword(sold by undead merchant) as an example the result would be a starter weapon that does 118 physical & 123 Magic with E/E/C scale rating which is comparable to Drake Sword at base with the added bonus of a better move set.
A +5 Magic Zweihander would do 196 physical & 212 Magic with E/E/C scale rating which pretty much Makes the Drake sword obsolete even at +5.
A +5 Magic Claymore would do 154 physical & 168 Magic with E/E/C scale rating making it noticeably stronger than a Drake sword at base up until +4.
Now the point of creating weapons like this is not for end game but rather to have as an overpowered starter weapon. The scaling in this instance doesn't really matter much.
Also you can find the Enchanted Ember early on in Darkroot Garden. In Darkroot Basin first make sure you get the Hydra to kill the blue golem things using it's projectile attacks. Then to kill it simply run into the shallow part of the water using the trees for cover so you can bait the Hydra into bringing down it's head. After that keep shield up & smack the heads after they come down. After it's dead use the latter to enter the garden from the back so you can get the ember. This is of course assuming you don't want to pay the 20k for the seal shortcut.
PS: The Blue golems drop Blue titanite Chunk which is needed for enchanted weapons.
Then if you really were persistent in farming blue golems you could gain say a +4 Enchanted Claymore which does 178 physical 183 magic E/E/A. This would be stronger than a +5 Drake Sword with an added bonus of a better move set & can be gotten before you even ring the first bell. However farming for a +4 enchanted weapon if you're not in some way an intelligence build is a bit overkill. I would suggest sticking to +5 Magic if you're willing to farm.
PPS: You can also go extreme overkill early on by making a catacombs run to +5 fire a weapon after gaining the necessary materials (9 titanite Shards & 11 Green titanite Shards)though this is a bit more dangerous.
You could get say a +5 Fire Winged Spear 172 physical 172 Fire which is slightly more powerful than a Lightning Spear with the added bonus of longer reach.
You could also get +5 Fire Zweihander which will net you 260 physical 260 fire damage. A nice beastly weapon to have before ever facing Hellkite on the bridge don't you think?
PPS: The Large fire & Chaos Embers for these fire weapons can be gotten after killing Quelaag if you make a trip to demon ruins(very dangerous if not experienced). Though the material for those upgrades are generally harder to farm early on in the game.