A nice type of footnote

Just \renewcommand\footnoterule using the (simplified) definition of the rule in the linked post. You have to do this before loading the package footmisc because it overwrites \footnoterule.

\documentclass[12pt]{article}
\usepackage{tikz}
\usetikzlibrary{fadings}

\renewcommand\footnoterule{%
  \noindent
  \kern-3pt
  \begin{tikzpicture}[baseline=-10pt]
    \fill[darkgray,path fading=east] (0,0) rectangle (.4\columnwidth,0.02);
  \end{tikzpicture}%
  \kern2.6pt
}

\usepackage[bottom,hang]{footmisc}
\setlength\footnotemargin{4.5pt}
\setlength{\footnotesep}{4.5pt}
\setlength{\skip\footins}{8mm}
\begin{document}
First word\footnote{One}, Second word\footnote{Two}
\end{document}

[EDIT: This answer does not change the footnote rule, but only change the footnote text and symbol colors]

Adding 3 lines into your preamble may give you what you want:

\documentclass[12pt]{article}
\usepackage[bottom,hang]{footmisc}
\setlength\footnotemargin{4.5pt}
\setlength{\footnotesep}{4.5pt}
\setlength{\skip\footins}{8mm}
%
\usepackage{xcolor}
\renewcommand{\thefootnote}{\color{orange}\arabic{footnote}} % change the color of the footnote counter
\renewcommand{\footnotelayout}{\color{orange}} % change the color of the footnote text
%
\begin{document}
First word\footnote{One}, Second word\footnote{Two}.
\end{document}

The output would be: