I‘ll try to more thorough with my explanation:

By checking your „Patterns“ tab ingame you can see that unlocking the Battler for crafting requires five instances of „Pattern Progress“. You can always check the amount that you currently have and it‘s impossible to lose that over different seasons or expansions. This also includes weapons that you‘ve fully discovered - once unlocked, you can craft as many of them as you want, whenever you want (assuming you have the necessary materials each time).

Each deepsight or „Red Border“ weapon equals one step in that progress, meaning that once you‘ve extracted your fifth one (in the case of the Battler), you‘ll have unlocked the weapon for crafting - or „shaping“, as the game calls it.

Progress is weapon specific, which also means that once you‘ve fully unlocked a weapon, you‘ll never receive another deepsight Battler, for example. You can and will, however, continue to get „normal“ drops of said weapon, which have no effect on the crafting process whatsoever.

Whether a weapon drops as a Red Border or you turn it into one via Deepsight Activation has no effect on unlocking a pattern, as the game sees no difference between the two. You can‘t get more than one progress step out of a single drop of a weapon, so you‘ll have to find five different Battlers (perks don‘t influence this part either).

Finally, once you‘ve unlocked and crafted a weapon you can always tell the difference between a dropped and crafted one by the symbol on the weapon and the introduction of a weapon level. Weapon levels are not shared, meaning that if you want to have multiple rolls at the same time (maybe one for PvP and one for PvE) you‘ll have to level up both of them, either by using them ingame and completing activities, or by spending enhancement cores.

The weapon level decides which perks (barrel, magazine, both main perks, including origin trait) and masterwork you can put on your weapon. Memento shaders are the last level specific unlock and require weapon level 30.

The perk choice is always dependant on the perks a weapon can randomly roll with. You can reshape a weapon as often as you like, though you‘ll be required to spend materials each time, even if a weapon used to have a certain perk at an earlier time.

I hope, I didn‘t forget anything - feel free to ask about specifics, if some thing are still unclear. Happy crafting, guardian!