Calibre Hybrid file "BOTH" not showing Display Cover.

[simoii]

Good day!

I have a Kindle Paperwhite 2021 Version 5.14.2 and Calibre Version 5.39.1.
I wanted to maximize the use of Calibre Content Server to download books to my kindle. i find it more of a hassle to plug the kindle to pc/laptop.
so here are some issues i encountered.

.mobi - has library book cover, no display cover (kindle standby)
(tried check/unchecked Enable sharing of book content via Facebook etc.

hybrid file - no library book cover, has display cover (kindle standby)
uncheck Enable sharing of book content via Facebook etc.

hybrid file - has library book cover, no display cover (kindle standby)
checked Enable sharing of book content via Facebook etc.

azw3 file - no library book cover, has display cover (kindle standby)
unchecked Enable sharing of book content via Facebook etc.

azw3 file - no library book cover, no display cover (kindle standby)
checked Enable sharing of book content via Facebook etc.

what i wanted is to have either a hybrid file or azw3 file to be able to display both library book cover and display cover. yes this can be done by emailing .mobi or transfer via USB. just looking into this in case there are ways to achieve this. thank you!