I’m actually pretty high on this for true solo. Yes, 4XP is a lot, yes you need an enemy in play at your location.
But you effectively ignore shroud and can pick clues from connecting locations. And most locations will only have 1 clue anyway, so 1 clue per action isn’t an issue.
And unlike Lockpicks, this one doesn’t exhaust or discard itself if you get a string of bad luck, so you aren’t at risk of losing your investigate asset.
Unfortunately it’s 4XP and green, so that limits who can take it, since you probably want at least 4 intellect for reliability, so right now that’s basically just Alessandra, Finn, Trish, and Bob Jenkins.
Maybe it works in Tony Morgan with the right ally? He is pretty bad at using the lockpicks, testing at “just” 5 where rogues usually expect to be at 6-8.