He stretches his hand in front, so, likely, it is still formed in front of him.
About who among Ninten, Ness and Lucas is the strongest:
Storywise: Ninten battled Giygas. Lucas battled Porky. Ness battled both of them at once. This gives Ness the edge here. Also, Ness actually managed to last long enough against Giygas to indirectly kill Giygas. However, Porky is such a minor threat compared to Giygas that it does not really matter whether Ninten or Ness battle Giygas alone or with Porky. Ninten had only two others to help him (Actually, if you do things out of order, you can reach Giygas with only two party members, or you can even battle Giygas with Ninten alone). Ninten had less help than Ness had. So, either of Ninten or Ness could be more powerful.
Gameplay-wise: Lucas is out of question because his stats are much lower than Ninten or Ness', and their PSI is just as good as his. Ninten has ludicrous stats (His Offense and Defense reach nearly 300, he has about 250 Speed. His HP is about 510, and his PP is nearly 400. Ness does not have as much of Offense, Defense or Speed, but his HP goes above 920, and his PP goes to almost 670. Additionally, Ness has PSI Flash Omega, which has a 40% chance to instantly defeat an opponent. However, Ninten can essentially double his Offense, Defense or Speed at once. Ninten's Powershield completely reflects attacks. Ninten's Powershield and PSI Shield are also completely indestructible, no matter how many times they are hit. So, it could be either of Ninten or Ness.