@Sept Adding a bit to the comments of Rang-Dipkin. To get S4: Photon V Adaptation, Atlas partisan is enough, you don't need to upgrade it to Atlas EX.
For S5: Skillful Adept Will, you also have an option to use weapon category change. First add Skillful Adept Will to a Rivalate gunblade, then change its weapon category to rod. It seems you already have a Rivalate rod, in that case this means you change it to Rivalate gunblade to get Skillful Adept Will and then switch it back to Rivalate rod. Maybe not very effective.
And a final point. Switching weapon categories initializes weapon potential. So should you already have the Liberated Fang Redux potential on your weapon, changing category reverts the potential back to the normal Liberated Fang. In this case, weapon category change is better to be avoided.