>>37841374No, the dragged out sound is literally just holding the "o" longer. Typed out, soodo is technically correct, but it's pronounced like sohdo. It doesn't change it into an oo/u sound like English does. If it were oo/u it would be written "sudo" or スド, which is not how ソード is pronounced.
Most of the romanization systems are funky like that, I'm just making sure people don't read it as "oo" when it's a dragged out "oh". Some systems would write it as Sōdo, some Soudo, and some Soodo. I don't like the last one because in english two "oo"s is not pronounced the same as it is in Japanese.