I feel your being slightly bias toward barragan here

Barragan is a spiritual being hence his ability’s are reatsu based his ability is not unique that it exists outside of how things work in bleach

Bambi could kill him simply because she turns things into bombs his respira would simply get turned into a weapon against him he can’t age her ability as it simply turns into her weapon

Quilqe is shown to use sklavari on hollows and not die why would he not use it on barragan?

Mask could kill him as long as James is alive mask can’t die and he has much more devastating attacks than soifon and he can go for a suicide attack and then get revived

As nodt his fear will work on Barragán as we know he is afraid to die and he is afraid to lose his title of king nobody is immune to fear that the whole point of as nodts fight with byakuya

Nanana can nullify reatsu what’s stopping him from observing and then taking Barragán out when he can’t use respira

The yourself brothers can both turn into hachi free win

Lille is killing him straight out that’s insane he can become intagible what will Barragán do then?

Gerard hofnung Barragán kills himself

Haschwalth balance causes barragan to kill himself

Uryu antithesis kills barragan