The size of the two of them is definitely playing a factor. They’re too big for a standard card and there’s no existing SKU for them to fit in.
Really, it’s an answer of “who knows?”. It could be like the Sonic three pack with Were-Sonic where we wake up tomorrow morning and learn that someone found this unannounced set at their Target. Or they could just not release them ever until they someday lose the license. Even if they just upscaled the 2.5” versions, not adding any additional articulation, it would at least be something. But even the 2.5” versions both got a single odd release each and now sell for hundreds on eBay.
In ideal situation, they’d just use the larger boxes of their Amazon releases as an easy way to get them out.
I’m still posting daily on my dedicated Birdo, Roy, Morton account on Instagram, hoping to annoy their social media manager into saying something to whoever can make it happen. But we’ll see if that ever pans out.