Yip, but it’s only very slightly blue, and it’s not really a lake. Lunar photographers will often massively turn up the colour saturation to tease out very subtle differences in colour. You won’t see the difference with your eye, but the slight shades are really there, and reveal differences in geology all over the moon.
It’s known as Ina crater. It’s very small and probably of volcanic origin. You may have seen Astro-biscuit’s youtube video where he hunted it down.