I'm a social creative GM who likes to run games with little to no prep. I use a lot of player input. If that appeals to you, you might use this style of "rumors," you can improvise at the table. If you prefer simulation or random generation, this isn't your cup of tea.
I call it folklore because my system is in the folktale genre. Folklore expands on the flavorful true/false OSR rumors we know and love with a dash of "unreliable narrator." It's very similar to the tables from Ultraviolet Grasslands. Here's the bones of it:
TAKE FOLKLORE WITH A GRAIN OF SALT. Though it blossoms from a seed of truth, folklore is re-imagined in retelling as common folk exaggerate and misre