Actually that's anti-twinking.
You use ship requisition to buy fleet requisition(the point of which would be to buy ships).
So essentially you're trading ship upgrades into ships for a fee. Though its actually fairly fast to earn ships anyways. Regardless, given the same number of games played, you end up with more upgrades on a ship if you don't convert and buy new ships, then if you do convert and buy new ships.
But you can also use fleet req to upgrade ship systems, so if I convert the req from ship A to fleet,
and use that fleet req to upgrade my systems on ship B, that would be the twinking part.
That's actually important to note: if you try to upgrade a ship system, and can't pay all with that ship's req,
the rest of the cost will be paid with fleet req.... So be careful, y'all, when upgrading your ships.