I do it all the time. Set of Armor are inventory item 277. You can cheat them in the moment you start the game.
You won't get any of the labels to show until they are at each location. And there is whole lot of repetition you have to get right. Current Mercenaries Total, Mercenary of each type total, total in each location, and All Mercs counted. Then you also have to work around the anomalies that are Frank and Dwain, this save has Frank, it doesn't have Dwain. You have to see it in action to understand it.
I literally only train one merc anymore. (Yeah, I am a big fat cheater, I also completed this part in v0.6.1.5Bugtest, v0.6.1.0, and several times between v0.6.1.0 and v0.6.0.5, I have no interest doing this all every couple of months.)
That is the only way to get a Mercenary 2 to show up anywhere. Then I equip him, long before John has made me a set of armor.
From there if I send the 3 to Arenfield, I should have a Merc3 spot in both camp and Arenfield in RpMakerSaveEdit. So I go in and just add everyone as 3's and delete everyone that's not. It can be tricky to get it right the first time, especially if Frank is artificially inflating Arenfield's numbers.
I have never broken any save with it. I have had to retry it several times until I got all the numbers right.
View attachment 5562555
Extra special bonus cheat.
Notice entry 1065, it's with the merc's though it doesn't say Merc's itself. You know what that is? It's how much of the forest the Merc's have searched for Yasmine. Go search for Yasmine, after your first fight with the Nightingale walk to the end of the screen. On the next screen, turn around at walk back, go home. There will be a number in 1065. Change it to 90. Sleep, search for Yasmine until you get the notification that your merc's found the camp. Go right and go back home. Go back into the forest to scout the camp. Go home and launch the attack. Should only take two days.
View attachment 5562591
how you got this save editor by that can i change the variable and get yasmine and liandra scene