I also recall Ness's shield being capable of reflecting the Starmen's Lasers, which should count as Energy Manipulation on some level.
Now, for the battle itself, i'll say Ness for some minor advantages.
For starters, Shulks precognition serves more like clairvoyance, the which is not likely combat applicable. Even then, Ness as also shown some level of clairvoyance during Earthbound, especially after gaining low 2-C power, since he was able to predict where his next objective is. That's one of the reasons he has Nigh-Omniscient intelligence in the first place, and is as likely as Shulks to kick in before battle.
Even if Shulk disables Ness's shields, is not like he can't keep putting them every time they go off. Also, the barrier art confuses me by the same level aspect, does it mean it by like, "same level power"?, becuse even Ness's weakest attack is Low-2C by default, and even when he's level 99, he can still use PK attacks at level alpha, wich is te weakest of them all, so by default, PK attacks at level higher like Beta and Omega should be above regular isn't? so in that case, stuff like barrier would still be useful?
Also, if Shulks barrier ware's off, he as to face the statust effects from Flash or stuff like Paralysis and Sleep, and with them activated, he doesn't have much options, since they will difficult him from using any of his abilities. Stuff like sleep pretty much make's him free hit's, Paralysis takes away his physical combat abilities, confusion make's him capable of hitting himself with is own art's, uncontrollabe crying means he won't hit Ness with any attack, and the chance of OHKO is obvious danger, even more considering that it as a 40% chance of hitting.
Also, Shulks abilitie to heal only cures some little, while Ness can go full in an instant
And finally, Ness's immortality is a problem, since even if Shulks manages somehow to destroy Ness, he will had to fight a fully recovered Ness again, while he will now be completly tired and wash out of eter by then.
