Hi, Ralph.
First, I've been retired for over a dozen years, so be sure to check with your own CPA, who should be up-to-date on current tax rules and property ownership rules of the state where you live.
Second, it's MUCH easier to combine multiple separate items than it is to divide up lump sums.
And, third, the exercise may be pointless or it may not produce the results you expect and can use.
Where (in the world) do you live? If you are in a community property state, you may be going to a lot of trouble to get useless answers - at least for the federal income tax return. Generally, property earned by either spouse is considered community income and belongs one-half to each spouse from the moment it is earned - and that's the way it should be shown on returns filed as Married Filing Separately. For example, if he earns $40,000 and she earns $100,000, then each filing separately would report $70,000. There are many other such provisions that most of us find counterintuitive - or even quirky. Trying to divide up interest paid on a home mortgage, for example, or dividing medical expenses between the spouses can run into some very unexpected rules.
Even in a community property state, though, spouses may own property separately. Such separate property might include assets owned before the marriage, or property received as gifts or inheritance by one spouse. Separate property remains separate unless it is converted to community property, either intentionally (such as by gift to the other spouse) or unintentionally (such as by being commingled so that it can no longer be separately identified). Change of form, such as converting stocks to cash to real estate, does not change the separate character of the property. Income from separate property may or may not be community property, depending on the state involved.
In both community property and separate property states, there are other forms of joint ownership, such as joint tenancy, partnerships, etc. The effects of each of these would need to be separately determined in each case.
Given all that, you still might be able to produce what you seem to need, which is a separate statement of financial condition for each of you, but it would take some effort - and, preferably, some advance planning. You would need to create different accounts for each group of assets (and liabilities), making sure to segregate them by the form of ownership: His, Hers and Theirs. Then you could create a Net Worth Report that includes all of His and half of Theirs, excluding all of Hers. If you wanted to produce separate income statements, you would similarly need to create separate Categories (in Quicken-speak) along the same line. Or it might be easier to use Classes to accomplish the same results.
Much of the answer depends on how you plan to use the information generated. Is all this for tax returns? Or for a divorce? Or to present to a banker or other lender or investor to support a business proposition?
I know this is not a complete answer to your question, but it should provoke some further thinking to clarify exactly what you must do to get the answer you need.
Whoops! I re-read your post and see that you specified the "AU version", so I assume that you live in Australia. I know NOTHING of Australian laws, including those about property rights. I probably should just delete my whole message, but I've already typed it out, so here it is for whatever use you can make of it.
RC