Why not "flip" the texture itself (horizantally) in MS paint? It'll look backwards, but just right in-game... Or was that done already?
Oh well. In any case, with a few tweaks here and there, I say you have a fine-looking ship anyhow. She looks somewhat TOS, yet somewhat TMP, but alright. The Okinawa-class is one of my favorite non-canon designs, and as I said, with some tweaks you'll do her justice in the TOS-era.