Orange tips also require a license in Aussie land I believe (weird)
It's State dependent. For My state:
"In the state of Victoria, devices that can reasonably be mistaken for working firearms based on their overall appearance (but do not have the functionality of a working firearm), are classified as imitation firearms. A Chief Commissioner’s Prohibited Weapons Approval or Governor in Council Exemption is required to possess, carry, use, offer for sale or import an imitation firearm."
Source: Police Victoria: Quick Guide to imitation, toy and other firearm paraphernalia
First photo on OP would, by nature of it looking tacticool, require a prohibited weapons approval. If it was in Nerf Yellow/Nerf Blue/Hello Kitty Pink/Combination of the 3 colours, it would be ok