I got a free, used 10 gallon tank.

I'm going to divide it for my 3 bettas. I'm wondering about a few things. I bought a Whisper 10i filter. I'm going to make my own dividers with the plastic canvas/craft mesh so I'll only need one filter. I'm planning on putting the filter on the side where my female will be, because she's a good swimmer, and I'm going to put Fishie, my largest HM male on the opposite end because he has a bit of trouble with filter current. Will the tank filter ok, even on the opposite end? The dividers must inhibit the flow a bit.
Also, I thought I read that this is generally a low flow filter. Is that right or am I thinking of a different filter?
I can start the cycle with filter media from my 5 gallon. The BB is also on the gravel too, right? I'm going to transfer the gravel over- will that also help start the cycle?
Also, how do I transfer my plants from my 5 gallon? Will they get all disturbed from me uprooting them? My rosette sword has been in the tank for about 5 months and I imagine it has a good root system. My Amazon sword also has been in there for a couple of months so the roots are probably established.
TIA!