Well first off, the first shadow is most likely a Mantine pre-evo (given that these are real pics). But think: just 'cause something evolves, doesn't mean it has to get bigger and more jagged. Maybe Mantine has a more compact, sleeker, areodynamic look for it's evo. 'Pac knows Mantine needs an evo, not a baby. Then there's the perspective variable. It's very possible the Poke' is positioned in a way that it looks like something it isn't. This ersatz Poke may not be a Mantine-anything!
2nd one: Everyone's already explained what it probably is, but I'll say what I think anyways. Grass/Electric (the tail looks like a tropical leaf to me), and those balls... maybe they're actually rings? An electric current, perhaps?
3rd: Parrot with Flag/Note(not likely)/Scythe(likely). I pray this is a Murkrow evo, 'cause I like the crow, but I just have better options. I would be happy to see all three of these as our starters, but given it's movie info, and starters are usually shown later, they probably aren't.
My conclusion: Fake (until confirmation), starters (which would be lucky), evo/pre-evos of already existing Pokes, which is the most likely. I would also say it's also possible they're new Pokes altogether, but that falls under 'starters'.
*Crosses fingers* Please be real!
~The One And Only Flux