Here's what I used. The statblocks are very abbreviated because I have no plans to publish.
BG2 Drow
All drow have +10 on saves vs. magic.
Drow Adamantine gear: Magic, not immune to critical hits.
Longsword +3
Plate +2 (AC 20)
Adamantium Shield +3
Elven Chain +3 (AC 16+dex max 2)
Light Crossbow +2
Adamantine Dagger +2
Drow poison: DC 13 Con save or be poisoned for 1 minute. If failed by 5+, asleep for 1 hour or until damaged or awakened
Drow Rogue
MM pg 128, “Elite Warrior”
CR 6
Dagger: +9 to hit, 1d4+6 piercing + sneak attack
Light crossbow +9 to hit, 80/320’, 1d8+6 piercing + sneak attack
Sneak attack 3d6
BA
Dash, Steady Aim, Disengage, Stealth, Apply Poison
(Dagger +2, Elven Chain +3, 2 doses poison, 1 greater healing potion)
Drow Warrior
AC 25 (plate+shield)
HP 60
Speed 30
Str +3, Dex +3, Con +1, Int +0, Wis +1, Cha +1
Saves Str +6, Con +4, +10 vs. magic, adv. vs charm
Skills Athletics +6, Stealth +6 (disadv)
DV 120’
Immunities: Magic sleep
Sunlight Sensitivity
Actions
Multiattack: The drow warrior attacks 3 times
Longsword +3, +9 to hit, 5’, 1d8+6 slashing damage
(1 greater healing potion, Plate +2, Shield +3, longsword +3)
2 wizards (I think I used the drow mage statblock and changed up spells a bit?), 1 rogue, 2 warriors were a tough fight for a party of 4x level 11s. Some of the toughness was suboptimal tactics, but the high-AC warriors tanked things pretty well just by having an absurd AC. The low HP across the board mean they are very fragile, IF you can connect. The party rogue has no Darkvision, and drow have Darkness to counteract the light spells, so he suffered. Otherwise he could have one-shotted any of them with a lucky 20.
Having played Baldur's Gate II many times, I felt like it really hit the spot of feeling exactly like that first battle against drow in the Underdark. You round a corner and there's a group of 6, and your egg-cracking spells are mostly ineffective. Attack-roll spells were mentioned above, and when you combo SR with drow magic gear, the attack roll spells didn't fare much better.
They just beat the Pit Fiend near the Svirfneblin city and got the Daylight gem, which I'm giving actual use to by having it cast the Daylight spell once a day. Between that and the party fighter now having AC 26 due to drow gear, a re-run of the battle would go quite differently... as it should, from a pacing perspective!