Well shiny breeding is similar to normal breeding except for the OT, also you can only breed shinies together
the OT passes if the main OT is you, so female usually or either if you are breeding with a ditto otherwise the offspring will be an UNKNOWN OT
I really like the idea and how much thought you did put into this, I hope they consider it even if they still need more ideas and will ask for more suggestions from us, many would love to help to add such fun experience to the game
so you want a 4x31 and a 5x31? try being a bit more specific I guess so people would now what you are looking for exactly, like 4x31 excluding sp atk for example, idk much about shiny breeding but that would've made sense for me to read at least
uh I also did this, feel free to change IVs that might be better as 31s I guess or shuckles ability/item cause it really was hard to see them through the video
shuckle @ Cat Cookie
Bold Nature
Gluttony Ability
222 spdef/42 def/ 246 hp
24/28/30/22/29/11
Encore
PowerSplit
Rest
StealthRock
Shedinja @ Focus Sash
Adamant Nature(I'd recommend Jolly I guess)
WonderGuard Ability
252 atk/252 spd the rest on hp for the memes
x/31/x/x/x/31
Agility
Baton Pass
Shadow Claw
Swords Dance
Umbreon @ leftovers
Careful Nature
Synchronize Ability
252 hp/252 def/6 spdef
24/11/29/25/24/3
Baton pass
Protect
Wish
Yawn
Vaporeon @ Leftovers
Impish Nature
WaterAbsorb Ability
252 hp/252 spdef/6 def
31/13/31/21/31/17
BatonPass
Protect
Wish
Yawn
Conkeldurr @ FlameOrb
Adamant Nature
Guts Ability
72 hp/217Atk/9spdef/212 spd
31/31/12/12/12/31
Drain Punch
Earthquake
Facade
ThunderPunch
Ninjask @ LeftOvers
Bold Nature
SpeedBoost Ability
252 hp/252 def/6 spdef
31/8/31/5/31/24
BatonPass
Protect
Substitute
SwordsDance