[Where to find a Dusk Stone]

I already checked the item location guide thread, but the dusk stone is not in the sub railnet ..

[Bunnelby Ability Capsule]

Recently I found a bunnelby with an adamant nature and decent ivs, which is really good but, whenever I use an ability capsule its ability is always changed to cheek pouch instead of huge power. Would I have to catch another Bunnelby for huge power?

[What good Pokemon can I acquire early game?]

Well the title says it all

[I accidentally received the wrong ability for my Torchick..]

While soft resetting for the right nature and speed boost, I forgot to check for my ability once I got the nature I wanted. Now I have a blaze torchic and i'm wondering if it's possible if it's ability can change early game.