On purchase there is the field invoice_address. But in most cases the invoice address of an incoming invoice should be an address of the company. So in most cases the field is just used to have a correspondence address for the supplier on the purchase report.
I can find only two valid reasons to have a invoice address on the purchase:
when there is a differing invoice recipient (which is already handled)
in the case of self-billing (the company is writing the document instead of the supplier)
Both cases do not describe the general case.
So think that the field name does not match the real usage of the field for the general case.
Do you have any idea what we could do about this ambiguity?
The invoice address on purchase is useful to correctly compute taxes when the rules depend on the countries.
So it is actually the address from which the supplier will send the invoice.
For me there is no ambiguity but we could have an help text that describe the field.
The effort of How to write tooltips should be completed.
Invoice address in purchase is an invoice address of the supplier. It is a mandatory field.
I think the invoice recipient address is less important.
Shipment and delivery addresses also influence tax application.