No date announced yet. Image source is from the official website. I will updated this when I find an English language article (edit: Crunchyroll source). Synopsis of the light novel source from AniList:
Makoto Misumi was an average, everyday high schooler, who found himself shipped off to another world at his parents' whims. Upon arrival, however, he's insulted by the Goddess for being too ugly and thrown into a desolate wasteland. He frantically searches for human warmth and connection, but can find nothing but monsters and inhuman settlers. When he finally meets companions he can trust, they turn out to be a pair of powerful perverts in a former dragon and a former giant spider! His high-octane, incredibly misfortunate trek through this foreign world has only just begun!
I stopped watching once I figured out the pattern would be Encounter strong enemy > beat strong enemy > strong enemy becomes sexy lady > repeat
How can this get three seasons?
That pattern doesn't really hold though. The third strong enemy becomes a sexy man. Seriously though, it's not the greatest show ever made but it is better than 95% of the isekai trash out there and isn't nearly as formulaic as you seem to think it is.