\useasboundingbox (-1.8,-2.3) rectangle (1.8,2.3);

\tikzstyle{box} = [ draw=black
                  , text width=1.2cm
                  , minimum width=2cm
                  , minimum height=1cm
                  , align=center
                  , rounded corners
                  , thick
                  , align=center
                  ]
\tikzstyle{arr} = [ -{Latex[round,scale=0.9]}
                  , shorten >=1mm
                  , shorten <=1mm
                  , thick
                  ]

\node[box] (ex) at (0.75, 1.75) {existing tool(s)};

\node[scale=2,inner sep=0pt] (designer) at (-1.25, 0) {\faUser};

\node[box] (new) at (0.75,-1.75) {new tool};

\draw[arr] ($(ex.south)-(0.2,0)$) coordinate (x) -- (new.north-|x);
\draw[arr] ($(new.north)+(0.2,0)$) coordinate (x) -- (ex.south-|x);

\coordinate (y) at ($(designer.north)-(0.2,0)$);
\draw[arr] ($(ex.west)+(0,0.2)$) coordinate (x) -- (y|-x) -- (y);

\coordinate (y) at ($(ex.west)-(0,0.2)$);
\draw[arr] ($(designer.north)+(0.2,0)$) coordinate (x)-- (y-|x) -- (y);   

\coordinate (y) at ($(designer.south)+(0.2,0)$);
\draw[arr] ($(new.west)+(0,0.2)$) coordinate (x) -- (y|-x) -- (y);

\coordinate (y) at ($(new.west)-(0,0.2)$);
\draw[arr] ($(designer.south)-(0.2,0)$) coordinate (x)-- (y-|x) -- (y);