One question worth asking honestly first: are these even solving the same problem? Mostly, no, and that's the actual answer.
Morningstar is built for researching and rating funds and stocks before you buy them, star ratings, analyst reports, fair value estimates. PnL App is built for what happens after you've already decided to trade, tracking the behavior and emotional pattern behind your actual decisions. They're not direct competitors so much as tools that sit at different stages of the same process.
Pair your research process with a behavioral layer that catches the decisions research alone can't predict.