usepackage[backend=biber, style=authoryear,
  bibencoding=utf8]{biblatex}
setlengthbibitemsep{0.5baselineskip}
addbibresource{Bibtex/mybib.bib}
DeclareNameAlias{sortname}{last-first}
DeclareNameAlias{default}{last-first}

renewbibmacro*{cite}{%
  iffieldundef{shorthand}
    {ifnameundef{labelname}
       {usebibmacro{cite:label}%
        setunit{printdelim{nonameyeardelim}}}
       {printnames{labelname}%
        setunit{printdelim{nameyeardelim}}}%
     iffieldequalstr{labelyear}{nodate}
       {printfield{extradate}}
       {usebibmacro{cite:labeldate+extradate}}}
    {usebibmacro{cite:shorthand}}}