Thank you for quick reply.
I tried as per your suggestion but my bluehost support team saying "we can't edit EXIM file because it may effect all the users under the BLUEHOST" 
is there any another solution for incoming and outgoing emails tracking for a domain?
I tried to search for filter file i found one under .cpanel folder its name is filter.yaml
PHP Code:
---
filter:
-
actions:
-
action: save
dest: /dev/null
filtername: Generated SpamAssassin Discard Rule
rules:
-
match: begins
opt: or
part: "$h_X-Spam-Status:"
val: 'Yes'
aren't there any coding to append here for incoming and outgoing copy of mails to tracking mail id ?
Please help me!
Thank you once again!