Any class recommendations for first time playthroughs?
Barb seems a bit boring but that’s what I would initially lean towards.
you asking about funsies or meta?
if playing for the first time just do what looks cool imo. people always give this answer as a platitude for every game ever made but unironically click whatever mfer looks coolest on the start screen and roll with it.
my very first character was a TERRIBLE summon necro who i beat normal with. then made a zeal paladin to see how a melee class played. this was in patch 1.08, well before summon necro was a viable build lol. the beauty of diablo 2 is honestly that it functions as a fundamentally solid RPG in a way almost the entire rest of the genre never managed to copy. playing a class all the way through the three difficulty levels solo self-found is actually FUN and can be hard as fuck. the degree to which the different classes feel completely different to play despite sharing the fundamental game engine building blocks is insane. it's genuinely a joy going from playing a ranged magic user to melee fighter, it plays completely differently, like you're playing a whole new game almost. this is a direct contrast to diablo 3 where all the classes basically feel functionally the same to play (largely a function of all class power being tied to weapon damage instead of innate skill strength)
diablo 2 is a game where you will absolutely end up making at least one (though probably multiples) of each class because they're all gr8 and have multiple useful builds each, so you don't have to "fear" gimping yourself by playing melee, you're not permanently tied to any one thing. you're playing an account more than you're playing individual characters. eventually you'll get cool items that allow wacky builds too, like a werebear sorceress. these aren't meta but they're fun as fuck.
the obvious drawback to having the classes be so unique is that it isn't balanced though, and is essentially impossible to balance. the ranged classes are basically dominant for general PVE play, even the very best melee builds can't compete at all in terms of kill speed at endgame.
d2 is sort of a solved game so there deffinitely is a fresh start/ladder restart meta, and that's basically to make a sorceress lol. she's the only class that gets teleport innately, and teleport is a massive, massive speed boost in this game (much much stronger than d3 movement skills if you have those in your head as a reference point). everything else sucks in comparison until you get enigma (the only item in the game that gives a permanent teleport skill to other classes) or can waste thousands of gold/your time without blinking to refresh charges on a staff with teleport on it (gold doesn't matter in diablo 2, but you do use it for equipment repairs, and do lose it on death, meaning the worse your gear the more you'll die, meaning you'll be less liquid and able to repair your gear efficiently).
the only plausible meta runner up to a sorc is the hammerdin (blessed hammer paladin), which is a great caster build, easily one of the strongest if not the strongest in the game, but using the charge skill and/or teleport charges is purely a speed loss over the sorceress. make a blizzard or meteorb sorceress, farm hell andy/meph/ancient tunnels until you have decent gear to make the other characters is pretty much the meta.
so if you want to be as efficient as possible: first character sorceress (focusing on blizzard if you know what you're doing/what enemies to just skip, meteor/frozen orb hybrid build if you want to be slightly weaker but trade it for relatively easily killing anything in the game/not worrying about elemental immunities which are ubiquitous in the hardest difficulty), second character smite paladin (use gear your sorc found for him, farm hellfire torches from uber bosses, trade them for runes, trade use runes for runewords or trade runes for other gear you need, on it goes).
if you just want a really fun first class: luckily i find the sorc rly fun to play so the meta being eternal and unchanging doesn't bother me, she's unironically my fav to play. other extremely fun classes are basically any druid build (they can do summons, be a shape shifting melee fighter, or elemental spell damage dealer), summon necro, javelin amazon (focusing on lightning), or trap assassin (also mainly focusing on lightning, but has easy access to a strong fire trap which makes her great at soloing stuff)