Belatedly, I want to chime in to agree with what others have said - this is the wrong Framer buff. It needs something to let it work against other TIs - this problem is
especially obvious in Coven, where Sheriffs and Investigators are more rare. On top of this, Investigators are probably already one of the weaker TIs in Coven, and this weakens them further, which they don't need.
I've posted several suggestions:
Here,
here,
here, and
here. Out of those I think the combination of suggestions in the first one is best. The ability to fool Lookouts, Trackers, and Psychics was already mentioned above, so I'll emphasize one other thing from that post I think would be cool:
If the Framer's target is killed by non-mafia means or lynched the next day, they show as a Framer in the graveyard (letting Framers or other maf claim Sheriff, lynching their target.) Alternatively, the target could show as Mafioso; there are advantages and disadvantages to each option. A third option would be to let the Framer choose what role they're framing as, which opens up way more strategic doors and possibilities but is a lot more complex.
This is a logical extension of the Framer's existing capabilities, and allows them to frame people in a way that matters even when there are no TIs. It lets the Mafia make aggressive accusations against a framed town member, then get "vindicated" by the results - or write a believable town will to make an actual TI who accuses and gets you lynched you look like a framer. It allows you to "confirm" yourself by catching mafia, or it makes confirmation via catching Mafia a bit less reliable.
The "non-mafia death" restriction makes them clearly distinct from the Janitor (and they also don't hide wills), but they can still serve an important role in opening up claimspace by making a dead townie's role less certain. It's more difficult for them than for a Janitor (since you can't just accomplish it by targeting the same person as the Mafioso, you have to either predict who will die to non-Mafia deaths, or get someone lynched; plus, since the will is still shown, the town might not buy it), but of course they do other stuff too and have unlimited visits.