It looks like the second Owarimonogatari TV anime would be a TV special which spans two days. According to the Monogatari Series official website, the anime will air from 12th-13th August. The website also revealed the anime’s latest PV. It not only teases the TV specials’ story, but also the theme song, “SHIORI” by CLariS.
The 2-day TV special will have a total of seven episodes spread across those two days. The official website also revealed that each day will air approximately two hours of anime for the specials.
The specials will act as the second season for Owarimonogatari, which in turn kicks off the Monogatari Series’ final season. It will follow the events of NisiOisin’s third volume of the series with the same title. The third volume includes the “Mayoi Hell,” “Hitagi Rendezvous,” and finally, the “Ougi Dark” story arcs.