Very Specific Cracking Method

I am very new to Hashcat so Im not surprised if this is a dumb question but...

How would I go about making an attack that would do something like 

XwordXwordXwordX...

Repeated on an on.

I would want the Xs to be replaced by ?a
And I would want the words to be replaced by words from a wordlist that would also have rules put through them like capitalize all, leet speak, and or anything?

Thanks