Of course there would be a Japanese sword in another world. Not unexpected at all.
And yes, jap isekai authors LOVE slavery, so that slave beastgirl also came as no surprise.
Even without referring to the raws, it seems clear that quite a few parts are being mistranslated (not to mention the spotty grammar). But that, too, is typical for this genre.
Was this translated with Google Translate or something? It is downright Zero Wing level Engrish.
And what is this guy getting all worked up over the inferior slave for? Shouldn't he be trying to get back to the obviously better girl who already has a crush on him?