There are two or three understandings you will find argued among Seventh-day Adventists. Some who see Jesus as more our example wants Jesus to have the sinful nature and gain victory over it. They say that Jesus had the nature of Adam after the fall. Others who see Jesus as more our substitute sees any of this as making Jesus ineligible to be the perfect sacrifice in our behalf, and sees him as havint the nature of Adam before the fall.. The church argued over this for centuries and formed a third view, which sadly has been divided over the book "Questions on Doctrine" and also there has been a growing in other churches of having forgot what the church came to and held for the past several centuries and are falling into these two camps that Adventism has sadly fallen into.
Many (not all) of our pioneers questioned the trinity. Due to this there was not much interest in this question until the 1890s when the trinity started moving from the periphery, as an unpopular option that you could believe, to a more central role. Mrs. White at this time began quoting from theologians who have been teaching the traditional view. There was one, I don't remember his name, but it has reminded me of the name of the author Herman Melville. The writer she quotes has given fantastic descriptions of the traditional view, and Mrs. White picks some of his best statements. Sadly, those who want Jesus to have and gain victory over the sinful nature have written books trying to make Mrs. White's quotes on this topic fit their view.
This traditional view says that Jesus has the weakness that sin brings, he could get hungry, sleepy, maybe suffer from colds etc. but did not have the propensity for sin. This view sees Jesus as having his own unique nature, and not the nature of Adam after the fall, nor Adam before the fall, although there were elements of both included in his unique nature. We are sinners because of our sinful nature. For some studies on this understanding may I recommend:
https://www.americanchristianministries.org/index.php/our-sinless-yet-sympathetic-savior-mp3s.html
https://www.americanchristianministries.org/index.php/preparing-for-the-latter-rain-21835.html
https://www.americanchristianministries.org/index.php/god-s-spiritual-gifts-for-the-remnant.html
There are also recordings from John Wood at Atlantic Union college especially if you can find recordings of his "Spirit of Prophecy Class" which studies this in Mrs. White's writings.
I like the words of Mrs. White in the communion chapter of the Desire of Ages and a quote from poet/philosopher Eli Siegel as descriptions/definitions of the sinful nature. Mrs. White's quote says "there is in man a disposition to esteem himself more highly than his breathern, to serve self to seek the highest place and often this results in evil surmisings and bitterness of spirit." Mr. Siegel's quote is "There is in every person a disposition to think they are for themselves by making less of the outside world." Jesus had the same frailties that we have but he in no way had this disposition. Satan needed to modify Jesus' temptations to deal with the lack of this disposition in his nature.
I hope this helps!