Slow down a bit. Aranea, Meenah and the other Beforus trolls are the PRE-scratch counterparts of the "Ancestors" on Alternia. They were the first people we know that played the game in Homestuck. They began when they were 13 but were so bad at it (since their soft lives on Beforus hadn't prepared them for it) so they spent 6 years in there before they decided to reset it (and Meenah blew them up). Since they are all dead now (well, almost) they are 19 years old forever.
But time works weirdly out there, so while Aranea spent millions of sweeps as a ghost, she met up with Meenah when the latter had only spent a few minutes there. For Meenah, when we were first introduced to her, it was as if she had woken up there immediately after their scratch, finding Aranea and the B1 and A2 people.
So Aranea sure is ancient. We don't know how much "time" she and Vriska and Tavros and Meenah and the others spent roaming paradox space in their treasure hunt but apparently Vriska has been there quite a while after she died, so in actual time she might be ancient too. All the A2 trolls are eternally 16 year olds btw :p And all the kids should be 16 now as well.
Do I make any sense?
Beforus A1 -> scratched into Alternia A2 -> created Beta Earth B1 -> scratched into Alpha Earth B2