I have a 2012 MacBook Pro (this model) and I have also inherited two Dell U2515h displays, which understand DisplayPort 1.2 (but not Thunderbolt). I'd like to use the laptop (running OSX High Sierra) to drive both displays (independently, not mirrored).
The laptop has a single mini DisplayPort/Thunderbolt socket and an NVidia GeForce 650M which supports DisplayPort 1.2. Under OSX this can apparently be used to daisy-chain Thunderbolt displays but not DisplayPort displays (c.f. this thread about comparable hardware), whereas under Windows 7/8 on Bootcamp, daisy-chaining does work.
Is there any dock or adapter that will take a Thunderbolt MST connection from the laptop and turn it into two different DisplayPort streams for the monitors? Everything I've found seems to come with a warning that it won't solve the problem if I'm running OSX.