Journalist:
I would love to know of any dramas or movies (even if the Tenno is just mentioned briefly)!
Here are some of Taiga dramas that I have watched featuring the Emperor role
Taiheiki - in this drama, the Emperor and Imperial Court would be the main subject (although not the main character of the story) as the plot revolves around the Emperor Go-Daigo wanted to restore back imperial in power from Kamakura Shogunate...then eventually resulted into the unwanted Two Emperor system in history of Japan (Northern and Southern Court)
Kirin ga Guru - this drama features Emperor actively involved in influencing the politics while not having executive power
Sego-don - Brief appearance of Emperor Meiji after Meiji government is founded...again not much dialogs because Emperor has no power in government administration
Taira no Kiyomori - This is set during late Heian period where the Court is still having executive power...therefore Emperor is actively involved in the drama...the grandchild of Taira no Kiyomori was also an Emperor
Yoshitsune - Same period setting as Taira no Kiyomori, but most of the involvement is from the Retired Emperor...the reign Emperor isn't much shown in the drama as the one with power is the Retired Emperor (which is also the rival/enemy of Taira no Kiyomori)
Hideyoshi - Emperor made a very brief appearance in the Tea Ceremony hosted by Hideyoshi but only shown from behind the curtain (as what done in other dramas/films involving this scene too)
In my opinion, Japan entertainment has no problem in portraying the Emperor as long as it is reflected truthfully to the historical fact or the widely known historical tales. For example in Taira no Kiyomori (which is based on tales), the Emperor Shirakawa was portrayed as someone incestuous and corrupt. Would you believe he slept with his son's wife and the child from that affair later be in the succession line?