I was thinking of doing the exact opposite, making Pathfinder companions in BG3. See how robust the character creation customization is.
That's actually really interesting. Obviously, PF has way more classes so with BG3 you'll need to rely on multiclassing to shore the gaps as much as you can. Here's some thoughts assuming we're only getting PHB classes in BG3.
Spoilers for WoTR Companions:
Seelah - Paladin - Oath of Devotion - probably the most straight forward conversion IMO
Camellia - Fighter / Cleric (Nature) or Druid (Land) - this is a fun one. A splash of Fighter to reflect Camellia's fighting prowess makes sense to me. However, her caster class is tricky as 5e doesn't have a direct equivalent to Shaman, which itself is a hybrid of Oracle and Witch. Mechanically, both Druid and Nature Clerics works, but I think a stronger case can actually be made for Camellia being a Cleric over a Druid. 5E Clerics do not need to follow gods for power - they just need to basically have enough faith in something to manifest divine power, whereas you'd expect a Druid to still show some kind of a deep connection to nature.
Wenduag - Fighter (Champion) - pretty straight forward conversion here too. Archery fighting style, Sharpshooter feat, and maybe Crossbow Expert (better for 5E meta, but Longbow is more true to her PF character).
Lann - Monk (Shadow) - I think Lann suffers because his perfect 5e conversion class - the Kensei Monk - is likely not going to be implemented. I didn't want to make Lann another fighter archer like Wenduag, so Shadowmonk is the next best alternative IMO. You won't be able to use Martial Arts with it, but with X-bow Expert + Sharpshooter + Shadow Monk mobility you do have an angle of play.
Sosiel - Cleric (Life or Light Domain). I think this one's straight forward, there's arguments for several domains which fit him best.
Nenio - Wizard (illusionist) - I think you can argue the case for any PHB wizard class for Nenio. I chose Illusions because that's her specialist school. If non-PHB is allowed, Order of the Scribes might be the best fit.
Daeran - Mechanically - Cleric (Life). Story - Warlock (Great Old One). This one is interesting to me because a Warlock would've fit Daeren better than an Oracle story-wise IMO, given what we find out. Mechnically, the Divine Soul Sorcerer is probably the best fit for 5E, but we aren't getting that in BG3.
Ember - Lore Bard / Warlock (Fiend) Multiclass. Lore bard roughly mimics her ability to hex via inspirations and cutting words, and incredible charm. Warlock represents her relationship with Soot. If we had more than PHB, a Celestial Warlock / Lorebard is probably more perfect for her, but without that I'm flavoring who Soot represents as a good fiend.
Regill - Paladin - Oath of Vengeance / Battlemaster multiclass - Oath of Vengeance is probably the closest Paladin Oath to the Hellknight, and Battlemaster is the fighter subclass that think reflects Regill's tactical approach to combat the best. Pretty badass multiclass for a badass companion.
Arueshalae - Ranger (Hunter) / Rogue - I think the Hunter Ranger makes the most sense given that Arue doesn't use a pet. The splash in Rogue (I'm thinking just 2 levels) is to get her Expertise, which reflects her abilities as a skill-monkey in WoTR.
Woljif - Arcane Trickster - very straight forward conversion.
Greybor - Fighter (Champion or Battlemaster) / Rogue (Assassin) - Slayers are basically rangery-rogues without spells, which kind of makes the fighter/rogue multiclass a pretty close reflection of what it is.
