But the way it was executed was way off and it's pretty bad. Now, they could've made a story about Nero was investigating a secret society who are involved in ritual killings. And follow rumors of a satanic festival that can grant them power. And have players play as Kyrie to help Nero with the mission.
But the whole thing doesn't make any sense, why she gave them the sword. And helped them with the Savior thing. If anything, she could've sabotage their operations by herself. And from how she plays on the Special Edition, she doesn't need any help from Dante. And how would they know what she looked like? And they're secluded into their town, and it's never confirmed that they have spies.
I already give you an answer on why she give them the sword and the rest lol
Let me clerify, the sword is uselles alone, in order for the savior to be activated it need dante blood and the Sparda
the Sparda alone can't do anything, trish and dante have the situation under control even whit the Sparda in sactus hand, also no one in the entire world would have been able to capture Dante and use it to form the savior s core, but than nero another descendent of sparda s blood was captured and things went wrong, nothing that big, Infact dante easy destroyed all the hell gate and freed Nero
Quoting Sactus: "oh it's you gloria, unfortunately you do not anticipated a discendent of sparda s blood and because of this boy now the savior will be completed"
So as you can see trish give them the Sparda to gaine they're trust and secure a position in the order council to spy on them and understand if they have bad intention like lady says or if they just collect devil arm to open a zoo like dante says XD trish dosent care if they have the sword because she knows the sword is useless and nobody can use the sword power, Infact only a descendent of sparda or someone who understand sparda s heart can use it s power
quoting sactus again: "the power of sparda, why don't you give me strength? I'm I not worthy?"
So as you can see the Sparda sword is useless, if you are not worthy of it something already proven by arkham not been able to transform the force edge into the Sparda despite having the two amulet
So, things only Changed when nero was captured, thris and dante didn't know vergil had a son, meaning another sparda descendent to use for the savior
Even dante himself tend to go undercover especially in the anime, in episode 09 death poker dante went undercover to lower king guard and understand who is this king demon
He could have easily killed everyone in the ship, but why kills innocent people whitout any reason? Even in the episode in which he infiltrate the prison, he could have easily destroyed the whole prison from the start and killed everyone but he didn't because he wanted to understand what the hell was going on in that prison
in dmc 4 not all the people in the order of the sword are bad, for example kyrie, credo and nero where good people they just follow Sactus order who is the real bad guy, that's why trish went undercover to find out the truth before slaughter innocent whitout reason lol
The game have some problem, but this things in the story make perfectly sense