Short answer: Usually yes, you use them in pairs, but the “pair” can be a media converter on one end and a fiber switch (or SFP in a switch) on the other, as long as both sides speak the same speed, wavelength, and optical mode. In a fiber link, the data is transmitted from one end to another, and fiber transceivers are. The idea is to get a small switch in both the shed and in the garage too where the new optic fibre (in purple) would be plugged in. For information, the switch showed in the house (blue area) is just for illustrative purpose, I need to buy one with POE capabilities.