Olintos are more bendable than their standard flats counterparts, but definitely not as bendy as their Low Tensions.
They're also voiced a little bit brighter than the standard flats. But not super bright or anything. Depending on your technique and pickups, it's kind of a smooth brightness, will still give flatwound bite and bark with clarity when you dig in, and still sound nice and big and round with the tone rolled off.
I have a set of the standard La Bella flats on my Olinto P4. (I forget if i have the .107s or .110s)
I have a set of the Olinto flats on my Squier P bass that i use to test pickups i wind and i really like them. I've used the Olinto Flats on a Squier Jazz bass with Nordstrand Big J Blades and it sounded nice and beefy.
I have an Olinto P5 on order that i'm getting with the Olinto Flats.
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As to Left-hand playability and gauge, i think it's a bit of a red herring. My other basses have either La Bella Tapes or La Bella Superpolished (.047 - .107) which are incredibly bendy and playable, and still, my Olinto P4 with the huge gauge stiff flats is my most playable bass that requires the absolute lightest touch to play. IMHO, fwiw, if the bass is set up properly for the strings, the thick & high tensioned strings are really easy to play with a light touch. That said, every bass and player is different so your mileage may vary.