Black Arachnia was my favourite part of Beast Wars once she was introduced, and BW is my favourite TF era so I guess you know where my vote is.
I was amazed and in absolute joy when they released info that BA was going to be in Animated, then the episode came and it absolutely delivered! In Animated she's great but still I don't think she can compare to the original, non-transmetal BA.
In terms of personality, yea BW BA was a little obvious; good girl forced bad, turned good. But thats what gave her so much depth! The fact that she wasn't complicated history-wise allowed for a lot more character depth.
Fighting, BW BA had little but used it to it's fullest extent. Animated Arachnia has it a bit easy weapon wise, she's got the mimic technique which in my eyes has always been a cop-out, I've never let any of my Pokémon use the move, I only ever use Ditto as a breeding partner and outside Pokémon I've never designed a copycat character. It's just too godmodey, which is why she almost beat Prime, she was effectivly using his team against him.
TM Arachnia seemed too unarmed, she kicked, she had a bitey string thing, and that was kinda it, apart from the telepathy which was ok, though a little tedious to believe.
Style... ke ke ke... BW BA wins completely.
In terms of looks, it's obvious the original was best, the Animated versions one huge visual homage to the original! You only homage something that's good and liked. Hence no resurrection of the Wheelie name in the figures. Yet...
In terms of attitude, BW BA wins again, just look at those quotes.
In terms of the way they fight, Animated is quite stylish, but I haven't seen enough of it to judge yet.
I do not believe in BM Arachnia. It's a myth designed to frighten small transformer loving kids...
She wasn't that great in BM, hence my not even counting her in this.