R12.2.5 - Is it possible to choose tax applicability based on PO distribution charge account natural

We are on purchasing 12.2.5 and we procure both taxable and non-taxable items.  When creating a PO without an item number, is it possible to not apply a tax code based on the natural account segment that was entered on the distribution?  I know this can get complicated when it is possible to have multiple distributions and charge accounts per line, but in our scenario it is always 1 distribution per shipment line. 

I know that we can default it if an item is assigned with a taxable value of "No", but in this case we are not using item numbers.

I also know that we can set up a 0% tax rate and apply that to a supplier and/or site, then configure the tax engine for Purchasing to consider a supplier and or supplier site classification tax before resolving to item or default purchasing options tax.