Is it a lens?

https://www.legacysurvey.org//viewer/?ra=52.7335&dec=-52.4712&layer=ls-dr9&zoom=14&ngc&const

Yep, a known one.

Where can I see whether it is known or not? In some cases DESI reports a lens, indicating it as “strong lens”, sometimes it does not.

It’s in a bunch of lens candidate catalogues (viewable in vizier). There’s also some observation logs for it where the proposals indicate a search for lenses.