Global Invasion: Why Can I Only Turn into a Kid?

[Portals + everyone transforms + System + lighthearted + funny + no female lead + slight everyone-loves-the-protagonist vibe] On Blue Star, Xia Ying woke up one morning and found herself transmigrated to a parallel world! After eighteen years in her new life, Xia Ying came to understand one thing. What’s the difference between someone without a dream and a salted fish? But a salted fish with a dream must be a rare creature indeed... Luckily, the System may be late, but it never fails to show up! [Abnormal energy detected in the world…] [Congratulations, Host, you have awakened… the Super Invincible World-Saving System… Error… Error… Error…] [Super Invincible World-Saving System awakening… failed…] Xia Ying: ?? [System attempting to reload… Success… System updated… Super Invincible Cute System!] Xia Ying: ???? Why do I keep getting this ominous feeling? “Wait a...” [Talent transformation being locked in. Drawing now. Success. Talent transformation: little boy!] Xia Ying: … Well, at least there’s still hope of getting stronger. “So the way I get stronger is by completing all your cutesy missions and acting cute?!” [Yes, Host.] Fine. As long as I can get stronger... “By the way, System, shouldn’t I be assigning these stat points myself? And why does my looks stat keep going up?” […] […Host, that’s a long story.]