Now in drag, ultimately acting as host (10)
I believe the answer is:
presenting
'acting as host' is the definition.
(eg to host a TV show is to present it)
'now in drag ultimately' is the wordplay.
'now' becomes 'present' (the present time).
'ultimately' suggests the final letters.
The final letter of 'drag' is 'g'.
'present'+'in'+'g'='PRESENTING'
(Other definitions for presenting that I've seen before include "putting on a show" , "job in TV" .)