If you don't have the means to get her to 3 stars, I would advise against it. And even then, she isn't as useful as she could be, as she clashes with the current meta. She will be more useful with the inception of the Kage treasures, whenever that is.
The main reason she is extremely strong in the Chinese version (I thought it was the HK version?) is because there, GNW Tenten has no battlefield cooldown, meaning that it is possible for you to execute her move on the first turn, if you have the ninja to get you chakra.
For us, she's not as useful. During round 2, it's more important to get out fast mysteries to interrupt your opponent, so you use chakra. Getting 60 chakra on top of that is hard.
She's a neat ninja, but for now, at least, she's going to be on the backburner.
That said, I got her 2 stars, just because I wanna be a ninja-mon master. I gotta catch 'em all, at least as much a f2p can get