Hi. Can I apply for a job in Australia even I am outside the country? Are there employers who are willing to sponsor me using Employer Sponsor Visa? Should I have my IELTS first before I apply for Accountant job? Appreciate your feedback.

In theory it is possible
. find employer who will sponsor
. employer and you apply re sponsored employee visa

ESVs are not assessed re points but check the section on immi re IELTS and both an employer and immi would have expectations of you being a match re engliush ability.

In practice, unemployment is growing rapidly in Australia and so there'll be an increasingly large pool of native english speakers seeking work where there is less and numbers seeking work will also be continually supplemented by graduating students.

And with that environment I can imagine employers more likely to consider someone already in Australia rather than get involved with the sponsorship process.