WA have a noxious species list you can find it on the following page:
Qantas and others can fly boxed fish for you. Obviously they need to be packed appropriatly. Airlines have been a bit weird about flying pets since COVID... I dont really get the reasoning...
Anything that you plan on bringing over must be inspected by quarantine officers upon arrival and prior to leaving Perth Airport. This is easy... Just call them up and let them know when your fish will be landing in Perth... They may or may not ask for flight numbers. It costs about $60.... Link below should tell you what you need to know.
Hope that helps.
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