Mid champs have a lot of possibility right now. I know my local meta had an emphasis on Yas, Diana, Liss, and Ori, in order of safety picks. Reasoning for the middle 2 was counterpick to Yas with assasination potential, and lockdown on rampant adcs, respectively.
I haven't paid particular attention doe because preseason is a terrible time for developing a meta, since there's inevitably broken shit.
Speaking of broken shit doe, Kayle is pretty broken in mid or top because rageblade is broken. Nashor's rageblade can blow up most adc by itself, and lategame Kayle is still a hyper carry. Nashors, rageblade, runaans, dcap, with situational last item (assuming whatever boots) is hard to deal with because you start proccing rageblade aoe on the runaans bolts, so you essentially get a ryze-like ult empowered e on auto attacks. Literally just watch everything blow up and call it a day. Speaking of Kayle builds, I think the aforementioned build could work for Kog better than a typical adc build, but I have yet to test it. Namely just because adc Kog takes far too long to come online.