AFAIK there are certain threshold / requirements when you need to register for VAT in country B when you sell from country A (Within EU).
You might also check OSS with your accountant if you haven't done it already.
My Maltese LTD had to register for VAT in︀ Germany for instance, since I had a fulfilment centre there. While I didn't need a︁ VAT number for each country I sold my products within EU. (D2C)
You don't need︂ to partner with a resident in each country, but it might make sense to have︃ a partnered accountant in the desired country when reaching certain volumes in those countries.