First of all, you're going to need the latest release of
FEFTwiddler to import the .fe14unit files I'm about to give you.
I've circled the Import Unit button in
this screenshot.
A) The children, you can get simply by marrying off your characters.
B) I'm assuming you're playing as Male!Corrin, so you'll have Female!Kana. Here's my
Male!Kana and Female!Corrin.
C) For the Revelations route/Route exclusives, you'll need
Izana and Yukimura and
Scarlet, thanks to myself.
D) The
capturable bosses, thanks to Omegablu.
E) The
amiibo units, provided by myself.
F) The
characters from Omegablu's custom DLC. You'll just need the .fe14unit files, which can be found in the OmegabluDLCV2/Unit Files folder.
G) The
characters from DeathChaos25's custom DLC. Again, you'll just need to find the .fe14unit files, which can be found in the fe14unitfiles folder.
For the custom DLC characters, you'll have to do a few extra things. Using JKSM, you'll also need to extract your extra data because you'll have to merge your extra data with the combined extra data from the link I'm giving you below. The reason why you need the combined extra data is because you cannot use the custom DLC characters without it.
1. Extract your extra data with JKSM.
2. Using the combined extra data from
here, merge your extra data with it. Keep it in your extra data folder that you got from JKSM.
3. Import your new extra data with JKSM.
4. Open FEFTwiddler. Go to File -> Open File -> select your save file. FEFTwiddler only supports the Chapter0, Chapter1, and Chapter2 files.
5. Find the Import Unit button in the Unit Viewer tab. Click it and one by one, start to import the units I've given you.
6. Save your changes in FEFTwiddler. Go to File -> Save File -> select your save file.
7. Import your save file with JKSM.
8. Open game and see changes.