Below is the answer to this question from several CFL observers:

O’Leary: Johnny Manziel. If the question was better chance of starting through the entire 2019 season I’d say James Franklin.

Landry: As it stands now, Manziel. The Alouettes invested a lot, remember. Don’t think they’d be prepared to scuttle the plan before they give him him a solid o-line to play behind.

Cauz: James Franklin. I at the very least have seen a successful body of work from James. Johnny has had the odd moment but my biggest Manziel memory is yelling at someone to get all the seagulls out of the way as I’m watching him play.

Nye: Do you believe Johnny Manziel will be back in the CFL? I’m not sure. There is nothing to indicate he won’t stick to the two year deal and if he does, he’s the guy in Montreal. I want to see him with a full off-season to work on the CFL game after committing late before training camp. Then he was traded at the start of the season. Let’s see Manziel in year two! Franklin barely won the back up job in Toronto. Is Marc Trestman as convinced as many Franklin could be the next best QB? More questions than answers for both these quarterbacks, though.

Ferguson: Franklin. The whole Manziel situation just seems too volatile to put any stock in.

Morris: I say Franklin. Who knows where Manziel will be next year?
IMO it should be Franklin, as he has shown more promise than Manziel. However, that doesn't mean that will be the case as the Argos are facing a possible management/coaching shakeup, Trestman seemed reluctant to reinsert him in the lineup after MBT had several dud games, and Kavis Reed has sold Manziel as the marquee name of the franchise.