I know people will not be fond of this idea but I will say it.
Can I suggest try using AI to enhance the characters and background that is already there? AI generation can help with replicating.
There is 3d character like either models used in the 3d classic before Frenni, Bonfie, and Chiku, or MMD which has what you would need. Yet I only noticed the MMD versions has Lolbit, FT Chica, and Shadow Bonnie skins bisides the 10 which I know of that have the BB model. There are visual novels that used MMD character models. Now that I recall there is one MMD model that FNIA studios used for William Afton in their novel. There is 4 MMD Bonnie skins(Bonnie, SpringBonnie, Shadowbonnir, and surprisingly Bunzo Bunny), 3 MMD foxy skins(foxy, mangle, lolbit), 2 MMD freddy skins(freddy, goldy), 2 MMD Chica skins(Cica, FT chica), MMD BB, and MMD puppet that I know of.