This new h.265 codec is still very young , and the relevant software or NLEs may need some time to improving themselves
Look at Cinemartin Cinec PLIN it is a plugin available for Adobe Premiere Pro and After Effects
"Currently supported on Adobe Premiere CS 5.5, CS 6.0 and Adobe Premiere Pro CC. as well as After Effects CS 6.0 and CC"
Not inexpensive, but it gives new life to CS6. Maybe Adobe might be motivated to do something along this line since there appears to be a market for perpetual licenses.
Thx for your recommendation , I will have a try. Also expect for this app you recommend , I found another called pav, which may load XAVC videos, and do have the H.265 output option , but it only convert into *.mp4