as i always say, magic is terrible but if you must, i recommend the moonlight greatsword along with farron flashsword and farron dart. also, affinity/pursuers is a great spell

I did a spell sword build, I call I the "Fire Bug" because it was focused more on pyromancy than sorcery. A fire infused long sword will see you through most troubles, I used a crystal sword too; but it was never stronger than the fire sword with a focus on Intelligence. Just as powerful actually, except in the Smoldering Lake where the crystal sword was a godsend. Then I switched to Faith and used a lightning infused longsword because lightning is more broadly useful, especially against dragons. With an infused weapon in one hand, and a spell catalyst in the other; it's a very engaging build where you have options to dodge, attack, or use a spell as you see fit. Equipping Sage Ring, clutch rings, and rings that increase pyro/sorcery/miracles damage output as a trade off to defense is risky; but you'll feel like badass.

The Crystal Rapier (assuming you're going Sorcerer) is a pretty good weapon, with some nice Int scaling. Don't have it, but I heard that a certain scythe from Ashes of Ariandel is good, too, and presumably that lightsaber thing from the Ringed City. The Crystal Chime lets you cast Miracles too, so you can use things like Tears of Denial, and it has a pretty high spell buff, too. Once you start getting higher Intelligence, the Court Sorcerer's Staff has S scaling. Some good spells are Great Heavy Soul Arrow, and Soul Greatsword. Homing Crystal Soulmass is nice too, but imo takes a bit too much Flower Points, for how often it should be used. Farron Dart is also nice, but only for finishing off enemies with low super low health. Finally, it takes a heck of a lot of Flower Points, and is really hard to use right, but Soul Stream looks [b][u]awesome[/u][/b]. Rings that increase attunement, and decrease casting time are recommended, with the Bellowing Dragoncrest Ring, as well. Finally: I am by no means a pro at builds. I can guarantee there are better ones out there, and I've actually been struggling to find a weapon too. Right now I'm using the Dancer's swords, because they're awesome. I also haven't finished Ashes of Ariandel, nor have I played Ringed City yet.

If you are pure intellect heres your choice weapons Moonlight greatsword Friedes Great Scythe Aquamarine dagger All the other int weapons are shit, if you ask me. Spells are up to you, but I personally run with flashsword, greatsword, dark edge, and farron dart. A swordsmen sorcerer if you will. Note: this is a pvp build, not pve

Depends. You want a pyro, Mage, or cleric type spellblade?