The thing to remember is that however fast the Flashes are going for most of the episode, there are moments where they're going ever faster. They are talking to each other, standing "still" for a great deal of time, but all that time they're moving, reacting, etc at an insane speed. But they they start running.

So when Jesse runs off to Earth 3 to get Jay, or they all speed up to fling lightning bolts, they're going even faster than whatever speed they're at to be able to get so much done in the micro-instants between "ka" and "boom"

There's a lot of moments in the episode that require hand-waving. Barry's statements imply that taking someone into "Flash-time" is a new power only he has, a side-effect of his return from the speed force. But Jesse tries it like it's no big thing, and is surprised that it doesn't work, likely assuming that she can't because she's starting to slow down.

Then there's the fact that they're traveling so fast, presumably faster than lightning - they shouldn't have HAD to toss three bolts at once - Barry could have just set three of them going himself, and the micro-moments between their arrival shouldn't have made any difference at all.

Then there's the whole "Oh, neither you nor the Quark Sphere are trapped in the Speed Force any more, but I'm sure that'll be just fine"

The thing to remember is that however fast the Flashes are going for most of the episode, there are moments where they're going ever faster. They are talking to each other, standing "still" for a great deal of time, but all that time they're moving, reacting, etc at an insane speed. But then they start running.

So when Jesse runs off to Earth 3 to get Jay, or they all speed up to fling lightning bolts, they're going even faster than whatever speed they're at to be able to get so much done in the micro-instants between "ka" and "boom"

There's a lot of moments in the episode that require hand-waving. Barry's statements imply that taking someone into "Flash-time" is a new power only he has, a side-effect of his return from the speed force. But Jesse tries it like it's no big thing, and is surprised that it doesn't work, likely assuming that she can't because she's starting to slow down.

Then there's the fact that they're traveling so fast, presumably faster than lightning—they shouldn't have HAD to toss three bolts at once—Barry could have just set three of them going himself, and the micro-moments between their arrival shouldn't have made any difference at all.

Then there's the whole "Oh, neither you nor the Quark Sphere are trapped in the Speed Force any more, but I'm sure that'll be just fine"