A good tax accountant can handle any entity whether it be a sole trader, a company or a trust.
But an inexperienced and/or incompetent tax accountant could provide poor advice on any of these structures no matter how straigh-forward they were.
No matter what entity or structure you are trading through you will need a competent tax accountant.
How do you find a competent tax accountant is the question?
 

It depends on what you need in an accountant @Hatty Bell 
Industry-specific expertise might weigh in as more valuable than being your bestie with the accountant if you are into e-commerce sales. I know of clients who have saved over $20k simply by getting the correct advice/consultation.

It really comes down to what you are wanting to achieve, pay and experience in professional advice.   

Most accountants or tax agents can assist a business owner / sole trader to complete their taxes. 

As a BAS Agent I would advise you to look at choosing an accountant like buying a business suit.
Is any accountant a good fit?
If you are a woman who wears a size 10 pant and size 14 business jacket, or a XS size as a man would you purchase a extra large suit and expect it to fit well?
What about the colour, length of the leg or button positions?
You wouldn't just randomly select any suit in the first store you go to and walk out with it - would you?

The same process applies to your accountant selection.

TIPS TO FINDING THE RIGHT ACCOUNTANT FOR YOU
Ask people in Facebook business groups or on Twitter who they use and why?
Does the Accountant "niche" in your career field? (The more they niche, the better they understand the tax law)
Do you like to talk or are you the silent type? Find an accountant you feel comfortable talking with. 
Lastly, check that they actually are registered as a tax agent by popping over to the Tax Practitioners Board website to look up their name and details. Its a wise move to ensure you are given the "right" advise!
https://www.tpb.gov.au/registrations_search