These were done in a way that the members of the mane 6 do something that isn’t their true talent, but do it in a way that goes with their element
Rarity with Pinkie Pie’s-Generosity
Rarity would probably be good at hosting parties in a more..mature setting, so upon the realization that her true calling is now partying she opens up a night club or rents some venue, and throws a party that everypony would enjoy. (Especially Berry Punch.)
Applejack with Fluttershy’s-Honesty
So.. I guess she could still be honest to those around her, but still have fun with animals. She’d be more about having fun with animals instead of Fluttershy’s calm and gentle approach, much like the way she normally has fun with Winona.
Pinkie Pie with Rainbow Dash’s-Laughter
She’d be the only one in the mane 6 (other than Twilight, maybe.) who could even be able to do Rainbow Dash’s job due to her disregard of.. well, gravity and other laws of physics. She’d just bounce from cloud to cloud, airborne due to balloons and using her tail as a propeller to steer and keep the clouds under control. How would laughter come into this? Because she’s still Pinkie Pie, and if anyone needs cheering up, she could literally come down from the clouds to make them smile. Or with her strange way of cloud busting.
Fluttershy with Rarity’s-Kindness
She has freaky knowledge of sewing. Everyone knows that. So maybe she’d be capable of combining that knowledge to be able to run a business to the same degree as Rarity. Kindness would come into play in her being patient to others ideas, and trying her hardest to create a design to the level that her client would want done. Or by just using her day to day attitude when talking to people.
Rainbow Dash with Applejack’s-Loyalty
She would be really good at Applejack’s job. Seriously, her speed combined with her strength would mean she would be able to buck the entirety of Sweet Apple Acres’ trees in a small amount of time over 10 seconds flat. She would also be damn loyal to the farm. If it were her orchard and Flim and Flam came along, they would of run away before they had time to charm the town. “Nobody f-cks with Rainbow Dash”.