The mods PackagedAuto and the submod PackagedExCrafting will be useful in automating recipes with 9+ ingredients. This will be most useful with Avaritia as autocrafting is not feasible. While the Auto Crafting Table will craft x recipe when enough items are in the inventory this does not work with the Antimatter Catalyst. Almost any way to automate inserting singularities, even passively, does not work without overflow. The only real way is to make 81 ME level emitters and I believe that may be too much for most. The current mod list does not have a per-item limit transport setting. Only detecting the total at best.

github.com/TheLMiffy1111/PackagedAuto
github.com/TheLMiffy1111/PackagedExCrafting

Both have relatively recent updates to the 1.12.2 version and are on MIT licensing.

linking the curseforge pages for later
https://github.com/TheLMiffy1111/PackagedAuto > https://www.curseforge.com/minecraft/mc-mods/packagedauto
https://github.com/TheLMiffy1111/PackagedExCrafting > https://www.curseforge.com/minecraft/mc-mods/packagedexcrafting
(also PackagedExCrafting only makes sense to add after the switch to Extended Crafting Nomi Edition in the LTS version, though I haven't tested this - it probably doesn't integrate into Avaritia)

I keep mixing Avaritia and Extended crafting together in my head. I meant as you said.

If you really want to automate the catalyst xnet comes to the rescue again. Just place down 9 interfaces passively providing the 81 singularities and connect them with the avaritia auto crafting table. Then specify in the xnet controller to put exactly 1 of each item in the table at the time. Wait until the catalyst is finished. Profit.
PackagedAuto would make all of this trivial and I don't think a little automation challenge should be the sole reason a mod gets added. Especially if it only comes into play at the very end of the modpack.