In southern california we had a name for when it rained ~1" and then got really hot afterward - "Earthquake weather".

I've asked various times and even asked LLMs if there might be some truth in the idea, but everyone assures me, same as you, that no, water doesn't affect plate movement at all.

try googling/whatever the term to correct any misinformation i gave, here.

eta: I see negative points for defining a term i heard repeatedly over two full decades of cognition. Similar to trying to google the definition, the resounding result is "no."