So, this is a mod that was made by Tirlititi on FF9, called Alternate Fantasy (he did post about it in ID at some point, and is also in RHDN and Qhimm. I think he hasn't updated in a while, but might do so in the near future? It'd be nice if he posted about it here as well, perhaps). It's a mod made for both Steam and PS1 versions (with the only perk of being able to recruit Beatrix permanently in the Steam version), and features a lot of changes. The only other two people I know from here that have tried it are @Kjata and @Hart-Hunt.
I've been playing intermittently, and I'm mostly trying to tackle it at the lowest level I can. I don't really have a way to organize time for a stream, so I settled for boss fights, where I show what I'm using before the battle (or after, depending), and I'll take this chance to excuse myself for the poor quality of the recordings. I've recently come to a stop because I feel I WILL have to grind to be able to fight Hilgigars...
You may have noticed I used the gil booster at some point to be able to acquire the equipment I wanted/needed. I simply decided I wouldn't be bothered by grinding in two of the ways I knew wouldn't affect my party's lvl: chocobo hot & cold till death, or soloing monsters outside of Treno with Marcus (having Dagger and Steiner dead so they won't acquire any exp, although I'm not sure if the Marcus/Eiko thing is still there, and I'd rather not affect Eiko that way). So I feel fine being a cheater in this case, considering I'm only after the strategy for the boss fights in a borderline-lowest-level-possible kind of playthrough.
ANYWAY, here it is.