I don't even think it'd be better if they were the aggressors, just make sure people understand that the ferals are thinking beings. I mean, look at something like the Elcor from Mass Effect. People don't claim that any porn of them is beastiality, because they're shown in both the main source and the porn to be thinking beings. So long as it's readily available info that either the feral is consenting or is the aggressor, it should be fine.
The problem seems to come when people don't have that info up front, and so immediately assume it's beastiality. If the ferals are shown to be speaking or knowledgeable of their actions, there should be no issue. And if there is, those people need to evaluate themselves and what they consider intelligent life.
I think it helps if it's apparent the ferals are at least portrayed as thinking beings i.e sapient. They don't have to have be sapient to a
human level or have their own civilization, and you don't have to be able to communicate with them, as long as they're shown as conscious and aware of what's happening and capable of acting in response to it. Even if they're nameless, this helps make them a
character.
Going back to Teraurge as an example, sexual encounters with the Poh-Ack (a sort of cross between a xenomorph and a Tyranid Ravener) are, let's be blunt, bestiality when you have sex with them, but even if they don't have human-level sapience, they have enough
personality that it doesn't feel so squicky. Poh-Ack are normally dangerous but have a quirk where, once they're defeated, they become completely submissive, even to the point of letting predators eat them alive without resisting, and if you have sex with a female one she's noticeably enjoying it and actively taking part by the end, so clearly she can think for herself, even if she can't overcome the racial trait that makes her completely submissive and psychologically incapable of resisting you if she wanted to. The fact that the scene describes her as "your partner" and suggests that you leave her sexually satisfied at the end mitigates the impression that you just fucked an "animal".
An even better example is the Caenemung, which is a unique (at least so far) NPC creature which is clearly sapient, but completely impossible to communicate with, despite the game's mystical power known as "the Understanding" that lets everyone communicate regardless of what language they speak (presumably it has no actual spoken language). You can actually impregnate the Caenemung if you're male and, on a later encounter, it will lay an egg in front of you and nod confirmation that you're the father. Keep in mind that the Caenemung is a giant, limbless, eyeless sea serpent (not to be confused with Naigad, a much less giant, limbless sea serpent with eyes that you can communicate with completely as well as have sex with as part of a deal).
