Those things aren't equivalent. Useful nuclear fusion (i.e. more electrical power out than in) has not been demonstrated yet, and probably relies on techniques and technologies that haven't been invented yet.
On the other hand, we know how to make high-voltage DC transmission lines -- the only real questions are: how much will it cost, and is there some way we can do it better and cheaper?
There have already been DC lines over 2,000 miles long built that run at 800 kV or more. That's already long enough to reach several time zones away, and it's not a conceptual stretch to imagine linking several of these together to reach further. According to wikipedia:
> In 2010, ABB Group built the world's first 800 kV UHVDC in China. The Zhundong–Wannan UHVDC line with 1100 kV, 3400 km (2100 miles) length and 12 GW capacity was completed in 2018. As of 2020, at least thirteen UHVDC transmission lines in China have been completed.
> While the majority of recent UHVDC technology deployment is in China, it has also been deployed in South America as well as other parts of Asia. In India, a 1830 km (1140 mile), 800 kV, 6 GW line between Raigarh and Pugalur is expected to be completed in 2019.[58] In Brazil, the Xingu-Estreito line over 2076 km (1290 miles) with 800 kV and 4 GW was completed in 2017, and the Xingu-Rio line over 2543 km (1580 miles) with 800 kV and 4 GW was completed in 2019, both to transmit the energy from Belo Monte Dam. As of 2020, no UHVDC line (≥ 800 kV) exists in Europe or North America.
So is nuclear fusion. You have provided no evidence or even argument that it is practical.
Proposing that you can compensate day night cycle with transmission is surely a joke, no infrastructure of such scale has ever been built.