I may not be the best person to answer this because I’m a pretty strict hard polytheist, so I’m biased. I know that Hellenistic polytheism is more soft by nature because it focuses on the era in time after the death of Alexander the Great when there was a lot of
syncretism between Greece and Egypt. Also, I’m sure there are soft polytheists out there who are practicing Hellenic polytheists, so I’m not going to say you can’t be a soft polytheist while practicing HP.
There is one problem with this question as it is that actually may help the person who is asking: the hard/soft polytheist distinction. In antiquity, it’s not clear that hard polytheism as we know it existed.
Gods were different from place to place, from time to time. The god that was known as Zeus in one place may have been much different than the god known as Zeus in another. Gods from different pantheons were associated with the gods in their own, to the point where they become one larger syncretic entity in and of themself that has aspects of the different gods.
Now the confusion comes not in pure syncretism between pantheons as seen in Hellenistic times, but the local differences between gods. Some gods that may have been seen as the same by the people in the places, or had identical qualities, may have been called by different names. Some gods may have had similar personalities and similar aspects but different names. To draw lines in the sand between gods that overlapped in such a way requires removing the overlapping characteristics from one god and only apply them to the other or vice versa.
A great example that I’ve personally been researching lately would be that of Artemis and Hekate, particularly as they were seen in Asia Minor. Both are child-bearers, both maidens who see over the transition to marriage, light-bringers, torch-bearers, who lead down paths. There are two goddesses who have such similar traits that sometimes you’re not sure whether they’re just similar or just the same. And that happens all the time in ancient texts! Hymns, prayers, you’ll find a bunch that refer to Artemis as Hekate and Hekate as Artemis, even using specific traits of one to refer to the other. It’s a weird grey area.
Let’s go even deeper, okay? The specific area of my research has to do with Anatolia. In Anatolia, the triad of Kybele-Hermes-Hekate was an equivalent to the triad of Leto-Apollon-Artemis, with Kybele and Leto both being versions of the local mother goddess of the area (who was merely referred to as “Mother”). In that time and place, Kybele and Leto were names for the same god, the Mother. Hermes and Apollon were names for the same god, the son of the Mother, and Hekate and Artemis were names for the same god, the daughter of the Mother.
With that in mind, how does that affect the hard/soft distinction? The mother and the daughter weren’t the same, no matter what you called them. The daughter, whether you called her Artemis or Hekate, wasn’t the same as the goddess who was called Athene in Greek. So it’s not the same as the Wiccan duotheism type of soft polytheism where all gods and goddesses are all one god and goddess.
And yet it isn’t completely different. Where does that leave us? At this point, I’m left questioning the whole hard/soft polytheism distinction as it relates to Hellenic Polytheism. It’s not necessarily the most historically accurate form of worship, despite sometimes being sold as more historically accurate way. It’s impossible to say how the ancients thought, since we aren’t them. But I think it’s important to keep examining and re-examining the concepts we sometimes take for granted and our relationships with them.
(Also, if anyone’s interested in that Anatolia information, I can direct you to some books and papers on the subject! It’s really quite interesting.)