Sony had a habit of doing things their way.
So I-link was their implementation of firewire. I recall that the composite jack was also a non-standard but that will need checking.
The s-video was standard I think.
I use a cheap and cheerful usb dongle from ebay, cost half nothing, has composite and s-video inputs and works fine for me from both camcorder and vhs players (via composite or with scart adapter) capturing direct to PD15.
I know some folk have had trouble with them but I've had a couple and they worked fine - even with old rubbish vhs tapes and with commercially done film to vhs transfer tapes.
If all else fails it's worth a look at.
Cheers
Adrian Life is really simple, but we insist on making it complicated. (see below)
Confucius
AMD Phenom IIX6 1055T, win10, 5 internal drives, 7 usb drives, struggling power supply.