If I use Greninja & Zoroark GX's "Dark Union GX" attack, can I put Honchkrow GX or other {D} type Evolution Pokemon GX directly onto the bench?
Yes, you can.
Source: Unbroken Bonds FAQ (2019-04-19), TPCi Rules Team (2019-05-02)

Relevant cards

Note: All applicable cards may not be listed below.
SM10_107
SM10_107
SM10_200
SM10_200
SM10_201
SM10_201
SM10_222
SM10_222