Naval Escort is not self-referential. Is NavEsc "1 location that would kneel to trigger its effect" as per the play restrictions of Ours for the Taking?
Can OftT ever copy NavEsc at all?
If yes, can other Warship locations be knelt as additional costs?
If they can, is it obligatory for the chosen NavEsc to be among the Warship locations that make up X?
No. OftT cannot copy Naval Escort.
Despite the fact that NE can kneel to pay its own cost, it doesn't have to. As such, it will not qualify as a location that "would kneel to trigger its effect" in general. The play restrictions for the "Any Phase" effect of OftT are therefore not met. For OftT to copy Naval Escort, the event would need to be reworked as a Response that would copy Naval Escort in an action window in which it had already been triggered (and knelt itself to pay at least part of its own cost).
Think of how Paper Shield can cancel Confession if the Holy character is knelt to pay the cost, but not if the 3 influence are paid. The variable in the cost has to be determined (by triggering the effect) before you know if the play restrictions on Paper Shield are met or not. It's the same sort of thing with Naval Escort/OftT: there is a variable in the potential cost of Naval Escort which would have to be determined before you know if the play restrictions of OftT are met. Because of the timing of OftT, that variable will never be determined when you check the play restrictions of OftT, so they are not met.
Edited by ktomThank you, ktom. What I figured.