There's an echo or two of series relevance in "Daedalus," but it's a rare episode from the arc-heavy season that's not only fairly standalone, but also almost skippable.
That's the general opinion, actually, but don't skip "Daedalus." Much like "The Ultimate Computer" from the original series, the basic plot involves a visionary scientist whose reputation is threatened by mishaps that threaten to derail his legacy. In this instance, it's an innovator in transporter technology.
As a prequel series, Enterprise has an opportunity to study familiar concepts from an unfamiliar stance. In the first season, transporters were a source of trepidation (only McCoy seems wigged out about them later, and Barclay, too, but they're exceptions). This is the first time in a while that the show has even put transporters in the spotlight. Ironically, the movie reboot that followed in the wake of the franchise flameout concluded by the final episode of this season also featured transporters as a standout element.
Anyway, another link from this standalone episode involves T'Pol learning about the death of her mother, whom we've only recently met. The whole plot of the episode could be seen as a parallel experience between the guest lead and T'Pol's journey, except I don't recall the main character receiving as much substantial attention as the guest. There's nothing inherently wrong about that, except the series does more relevant character work, and certainly with T'Pol, elsewhere, so the material here is comparatively weak.
"Ultimate Computer" isn't the only episode "Daedalus" resembles. In a lot of ways, it's a fairly generic franchise story. But it's worth watching, and you can pick your own way to see how relevant it can turn out to be.
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Memory Alpha summary.