With BLW you just offer regular food right away, so I don't see why you couldn't offer the veg. Once they are 6 months you can pretty much offer anything. Though different parts of the world will suggest delaying different foods like peanuts, other nuts, eggs, etc. They are still undecided about whether delaying foods (like peanuts) makes a difference though. I delayed offering gluten and wheat because OH has a family history of celiac, but that's it.
Common allergens are: nuts, wheat, eggs, strawberries, dairy & soy.
Some things are a little hard to digest at first (like beans) but that's just because their digestive system is just starting to work! xx