there are none that are easier or harder. you should wait until she has two full financial years of trading before considering applying, without it the application is inherently weak so you are just wasting your time.
Most of them are going to want to see the tax returns. She would have to be self employed for a long time before automatic assessments will overlook getting those.
*exception. go to the bank where you have your home loan. There isnt a good reason why they wouldnt give her a credit card, provided that she is a joint applicant and you have a good payment history. If they give you the spiel about minumum 2 years trading you are dealiing with dropkicks, ask to speak to someone with a bit of silver in their hair (you know, someone that grew up when common sense was a thing)