... lye, oil and EO will be referred to in mls and NaOH will be referred to in grms...
How you PACKAGE a product is one thing. How you MANUFACTURE a product is another matter entirely.
In the US, solid materials are usually labeled by weight and liquids are labeled by volume, and I believe it's the same in the EU. That means there is not much if any difference between Australia and most of the rest of the world on that point. In chemical manufacturing, however, one must have a reliable, repeatable way of measuring ingredients, and weight is the best way to achieve that when making soap.
You cannot assume milliliters are interchangeable with grams unless you're talking about water, and that's only considered to be true in everyday usage, not in an analytical chemistry lab.
Soaping oils and most essential oils (EOs) are less dense than water. That means 1 mL of an oil or an EO is
not at all the same as 1 gram of either. If you weigh out 1000 g of soaping oils in to one pot, and you measure out 1000 mL of oils into another, you will end up with quite different amounts in the pots. That means any soap recipe in mixed units (weight and volume) is not the same recipe as one using only one system of units (weight OR volume).
Last but not least, the saponification value is a weight-based value. You
have to use weight units for the oils and lye to make soap correctly if you want to use sap values as your basis.
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Here is how I would modify your spreadsheet to use lye concentration instead of "water as % of oils" to calculate the amount of water for a soap recipe.