Himeji to Nagoya using Kansai Wide Area Pass

Hi! Will the above trip require an additional fare if i ride the hikari train which is an option of the pass?

Please help. Thank you.

Of course - Nagoya is not in Kansai at all.
Did you see the coverage map on:
https://www.japan-guide.com/e/e2361_08.html
?

It seems to me you are conflating the Kansai Wide Area Pass with the Kintetsu Rail Pass.
https://www.japan-guide.com/e/e2357_006.html
http://www.kintetsu.co.jp/foreign/english/ticket/

With the latter, you can go all the way to Nagoya, but not on any bullet trains or even limited express trains.

No shinkansen covered.

Local and rapid trains covered to Maibara. Slower option though.

Google maps or hyperdia will net result for rhe uncovered area.

�tNo shinkansen covered

All shinkansen in unreserved cars are available from Shin-Osaka to Himeji http://www.westjr.co.jp/global/en/ticket/pass/kansai_wide/