Please, Can we have a repeat last action shortcut key command which allows you to duplicate your last transformation and is especially useful when you're copying objects and want them to be spaced an exact distance apart.  
this has been asked about before I believe 
https://inkscape.org/forums/questions/how-to-repeat-the-last-action-in-inkscape/

Feature requests: https://inkscape.org/forums/beyond/how-to-report-bugs-or-request-new-features/

It is worth submitting a feature request, or adding your "me too" to an existing request. This is how the developers know what users would like.

In the meantime, the Duplicate button and Transform dialog can cover some of that functionality. 

thanks for that I have created this new feature request.

https://gitlab.com/inkscape/inbox/-/issues/3676