If I equipt 2 charms on my rogue, and I'm only using the sword...

...will the charm stats still work; even though I'm not using the charms for spell dmg?

only the main charm (first slot) will give all the stats at full power
the acc slot charm (second slot) will only give charm power like heal or attack power on it working at 75% of total power, no stats like hp or str/dex will be given

Also, when you solo, and are trying to use your Accessory Slot charm, it will cost 100 % of the mana and only work at 75 % efficiency.
As opposed to the catacombs, where it will cost 75 % of the mana and deal work at 75 % effectiveness.

Typically accessory slot is for a heal charm.

Does enhanced effect on charms apply when using a sword?
Does enhance dmg to sword swings too?
I'm just not sure if enhanced effect charm stats (both 2 slots) give +% more dmg to swords.

no, it doesnt

your ee on sword will ony affect the sword
ee on charms only affect on dmg of the charm