Now, regarding the suggestion to set different prices for non-EU vs. EU buyers, you can already accomplish this right now, without needing to create duplicate products nor maintain separate seller accounts.
One approach would use the &amount= parameter on your button URLs to boost the price on your EU buyers' purchase button URLs. With this approach, your products' Price settings would be the non-EU price, so you'd just use your regular button code for non-EU buyers. For EU buyers, you'd provide separate buttons for the exact same products, but these button codes would include an &amount= parameter to add VAT overhead to the item's base Price setting.
For Add to Cart buttons, the specified &amount= value gets ADDED TO the item's base Price; however, for Buy Now buttons, the &amount= value OVERRIDES the item's base Price setting as long as the &amount= exceeds that base Price. E.g., an Add to Cart button that adds an extra 12.34 to the base Price would look like this (where XXXXXX is your E-junkie Client ID and YYYYYY is your product's Item Number):
<a href="https://www.e-junkie.com/ecom/gb.php?c=cart&ejc=2&cl=XXXXXX&i=YYYYYY&amount=12.34" target="ejejc" class="ec_ejc_thkbx" onclick="return EJEJC_lc(this);"><img src="//www.e-junkie.com/ej/ej_add_to_cart.gif" border="0" alt="Add to Cart"></a>
A different approach would use our "Variants having individual price/weight/stock/SKU" feature, where you'd set up each product with Variants to determine EU vs. non-EU prices. This has the advantage of allowing you to update prices in Seller Admin later without having to edit any button codes already in your page, as long as you don't change the corresponding option values for your Variants. To follow the examples I'll provide here, you'd want to familiarize yourself with our Variants configuration as described here:
E.g., a product with an EU price of 30.00 and rest-of-world (ROW) price of 25.00 could Define Variants with Option 1 Name = "VAT" and a configuration like this:
A neat trick here is that you don't need to depend on buyers to select the proper product option from a dropdown menu; rather, you can provide separate Add to Cart buttons for EU and ROW buyers that hard-code the proper option into their respective button URLs -- this tutorial explains this general technique in more detail:
E.g., following the example Variants configuration above, your Add to Cart button for EU buyers would look like this (again, where XXXXXX is your E-junkie Client ID and YYYYYY is your product's Item Number):
<a href="https://www.e-junkie.com/ecom/gb.php?c=cart&ejc=2&cl=XXXXXX&i=YYYYYY&o1=Y" target="ejejc" class="ec_ejc_thkbx" onclick="return EJEJC_lc(this);"><img src="//www.e-junkie.com/ej/ej_add_to_cart.gif" border="0" alt="Add to Cart"></a>