Other possible things to try (you may have tried these already, but it's worth a shot):
- Check your GF menu; find out what your GFs are learning and whether there are any useful junction abilities you haven't taught them yet. Setting them to learn something new and then having to battle enemies for AP might be a bit tedious but could be useful, especially if any of your party members don't have HP, Str, Mag or Spr-J yet.
- See if there are good spells you can draw from nearby monsters for junctioning, or if you can refine any good magic from items/cards in the Ability menu, using refining abilities your GFs have learnt. Might also be worth checking if you can change around your current spell junctions in a way that prioritises the stats that are best for the Edea fight - e.g. you'll want high Spirit for magic defence.
- Spam GFs? This is a pretty tedious method, but it's how I ultimately beat Edea on my first playthrough, when I did not understand junctioning at all; hopefully the fact that you have been junctioning would make it slightly quicker for you than it was for me! If any of your GFs have learnt Boost, you can use that to increase damage (although apparently it's trickier to raise damage amounts in the Remastered release?). I didn't know how to boost the first time I played either, though!
- Even if you're not GF spamming: if a character's in serious danger, try setting them to summon a GF, as that means the GF will take damage rather than the character in the lead-up to the summon.
- As enemies level up with you and become more challenging, I don't recommend grinding unless you really need AP for GF abilities. However, if your party's average level is over 30 already, see if you can encounter Tri-Faces in the Galbadia Garden lobby. When Tri-Face is over level 30, you can draw Flare from it. Draw a bunch of Flares, then run; Flare is great for junctioning to strength, HP, magic or elemental defence (it reduces damage from fire, ice and thunder). Tri-Face is fairly powerful, so feel free to run once you've drawn your magic if you don't want to bother with actually defeating it.
no subject
- Check your GF menu; find out what your GFs are learning and whether there are any useful junction abilities you haven't taught them yet. Setting them to learn something new and then having to battle enemies for AP might be a bit tedious but could be useful, especially if any of your party members don't have HP, Str, Mag or Spr-J yet.
- See if there are good spells you can draw from nearby monsters for junctioning, or if you can refine any good magic from items/cards in the Ability menu, using refining abilities your GFs have learnt. Might also be worth checking if you can change around your current spell junctions in a way that prioritises the stats that are best for the Edea fight - e.g. you'll want high Spirit for magic defence.
- Spam GFs? This is a pretty tedious method, but it's how I ultimately beat Edea on my first playthrough, when I did not understand junctioning at all; hopefully the fact that you have been junctioning would make it slightly quicker for you than it was for me! If any of your GFs have learnt Boost, you can use that to increase damage (although apparently it's trickier to raise damage amounts in the Remastered release?). I didn't know how to boost the first time I played either, though!
- Even if you're not GF spamming: if a character's in serious danger, try setting them to summon a GF, as that means the GF will take damage rather than the character in the lead-up to the summon.
- As enemies level up with you and become more challenging, I don't recommend grinding unless you really need AP for GF abilities. However, if your party's average level is over 30 already, see if you can encounter Tri-Faces in the Galbadia Garden lobby. When Tri-Face is over level 30, you can draw Flare from it. Draw a bunch of Flares, then run; Flare is great for junctioning to strength, HP, magic or elemental defence (it reduces damage from fire, ice and thunder). Tri-Face is fairly powerful, so feel free to run once you've drawn your magic if you don't want to bother with actually defeating it.