TTL to USB (CP2102)(Driving 5V USB)
The USB protocol makes a strict distinction between hosts and devices, and does not allow two of the same kind to communicate with each other. A USB bus always consists of a single hub, and an arbitrary number of devices that talk only to the host.
That null modem cable contains two devices, i.e., two USB-to-serial converters, where the serial data lines are connected directly to the other device. This cable works only with two hosts.
If you want to connect a microcontroller (or whatever it is that uses TTL) to a computer, use the USB-to-TTL adapter together with a plain USB-A-to-USB-B extension cable.