I've no doubt about that but the real problem is there's a certain possibility that my enclosure fails with its esata outgoing signal. If it is then a PCI won't work because it will have nothing to convert to.
I joined http://www.fantec-forum.de to tell my issue to them especially for the potential damage about usb-esata chips told above by Paul. I'm waiting approval to open my thread...

@Paul
As said my mobo has no esata port, only 6 sata ones. I can only keep my bios firmware up to date but I doubt something about an esata improvement will be done, anyway as you said there wouldn't be issues for a sata port to recognize an esata input, would it?