My apologies if my formatting is terrible, and if this is a daft question.
I'm relatively new to Pathfinder and couldn't find any rules regarding this, but I may have been searching terribly, or used the wrong terminology.
I have a Sanctified Inquisitor with Two Weapon Fighting, and he's holding 2 daggers, one is a 'normal' melee attack dagger, the other has the Returning property.
Is there any problem with rolling a melee attack on my first attack with the first dagger, and then throwing the second dagger as my second? Both will have the -2 penalty, but other than that, is there a problem? Is this something I can do?
There's no problem; you can make your attacks however you like, as long as it's one with each weapon. You can even vary which hand you use first from round to round.
(BTW, you have wandered into the ill-labelled subforums for the PF 2nd Ed Playtest; there aren't many readers here now, so you'll want to direct any followup questions to Rules Questions.)