The time component is always implicit in both a vanilla short position or a synthetic option-based short. It's just easier to "see" in vanilla options, because

The time component is always implicit in both a vanilla short position or a synthetic option-based short. It's just easier to "see" in vanilla options, because it's priced in explictly. If you don't want to pay the cost up front by using long-dated options, just buy short-dated ones and roll them. The costs are likely similar as long as you construct the synthetic short position correctly. https://en.wikipedia.org/wiki/Put–call_parity https://en.wikipedia.org/wiki/Put–call_parity i.e. When you short a vanilla equity, you'll likely have transaction cost of borrowing the stock as an interest rate over time. This cost is incurred as you keep the position open. This cost is related to the cost of capital for the shares you've borrowed. Cost of capital is an implicit cost on time. To construct a synthetic short (using options/bonds), you basically short a synthetic equity. A synthetic equity can be constructed through a long call position, short put position, and long bond position. This synthetic will mostly replicate the the stock's return. To turn it into a synthetic short, you just do the reverse, short a call, long a put, and short a bond.