Do you reckon edmund feels any affection for either of the sisters?

I think this depends on two factors– 1) how does Edmund view himself, and 2) how fast was everything going down in King Lear

Edmund likes to talk very pridefully, but we’ve also got “yet Edmund was beloved” – something that comes off as almost surprised that he was loved. It seems to only occurs to him as he’s dying just how real the Lear sisters’ affection for him was.

for the majority of the play he’s stuck in tunnel vision, solely focused on destroying the Gloucester household and getting the Earldom. Given the timeline, if it all happened as quickly as it feels like– then he goes from being at the very outskirts of what could be considered nobility and someone who’s constantly degraded by those around him, straight to being the Earl.

Psychologically, I don’t think it even caught up with him that the king’s daughters could be potential dating options for him. As much as they blatantly flirt with him, it’s standard enough for nobility to have affairs (and Edmund would know that better than anyone–). So being considered an equal worthy of a real relationship with them is a fact that would take more time to sink in.

in short– I don’t think he considered either of them as potential dating partners until either when he was dying or sometime earlier in that scene.

and either way, the change in his own social status would have been a massive paradigm shift for him.

I do believe that he could have developed feelings for either of them, but I don’t think enough time passed over the course of the play for that to happen yet.