Posicionamento de tikzpicture completo em relação à coordenada

Question

Existe uma maneira de anchorcompletar tikzpictureuma coordenada específica com argumentos north, east, center, ...? Configurei uma grade mostrando as coordenadas do fundo ao ser ativada na opção frameby g. Então desenhei uma imagem tikz em cima dele (neste caso em (0,3.5)), que é o canto superior esquerdo do meu slide do projetor. Agora eu me pergunto como alinhar verticalmente a imagem tikz completa em 0,0 com âncora westou em 7,0 com âncora center. Eu geralmente uso overlaypara poder desenhar tikzpictures de forma independente em meus slides.

Código:

\documentclass[8pt,aspectratio=169]{beamer}
\usepackage[british]{babel}
\usepackage{tikz}
\usetikzlibrary{shapes,shapes.geometric,arrows,fit,positioning,arrows.meta,arrows.spaced,angles,quotes,decorations.pathmorphing,decorations.shapes,decorations.text,patterns,overlay-beamer-styles,external,calc,math,backgrounds,automata}

\tikzstyle{every picture}+=[overlay,remember picture,shift={([xshift=1cm,yshift=-0.41cm]current page.west)}]

\defbeamertemplate{background}{mydefault}{%
    %
}
\defbeamertemplate{background}{g}{%
    \begin{tikzpicture}
    \foreach \y in {3.5,3,...,-3.5}
    \draw[opacity=0.3,line width=0.1] (0,\y) -- (14,\y);
    \foreach \x in {0,0.5,...,14}
    \draw[opacity=0.3,line width=0.1] (\x,3.5) -- (\x,-3.5);
    
    \begin{scope}[opacity=0.4]
    \foreach \x in {0,1,...,14}
    \foreach \y in {3.5,3,2.5,...,-3.5}
    \node[font=\footnotesize] at (\x,\y) {\x, \y};
    \end{scope}
    \end{tikzpicture}%
}

\BeforeBeginEnvironment{frame}{%
    \setbeamertemplate{background}[mydefault]%
}

\makeatletter
\define@key{beamerframe}{g}[true]{%
    \setbeamertemplate{background}[g]%
}
\makeatother


\begin{document}

\begin{frame}[g]
    \frametitle{Agenda}
    
    \begin{tikzpicture}[Numbox/.style={rectangle,draw=magenta,fill=magenta,text=white,font=\bfseries,text width=12pt, minimum height=28pt,anchor=north west,align=center},
        Textbox/.style={rectangle,draw=magenta,text width=7cm, minimum height=28pt,anchor=north west,align=left,font=\bfseries,inner xsep=9pt}
        ]
        
        \tikzmath{
            \numskip=9pt;
            \textnumskip=3pt;
        }   
        ]
        
        \node[Numbox] (I) at (0,3.5) {I.};
        \node[Textbox] (IT) at ([xshift=\textnumskip]I.north east) {Problemstellung und Forschungsfragen};
        
        
        \node[Numbox] (II) at ([yshift=-\numskip]I.south west) {II.};
        \node[Textbox] (IIT) at ([xshift=\textnumskip]II.north east) {Problemstellung und Forschungsfragen};
        
        
        \node[Numbox] (III) at ([yshift=-\numskip]II.south west) {III.};
        \node[Textbox] (IIIT) at ([xshift=\textnumskip]III.north east) {Problemstellung und Forschungsfragen};
        
        
        \node[Numbox] (IV) at ([yshift=-\numskip]III.south west) {IV.};
        \node[Textbox] (IVT) at ([xshift=\textnumskip]IV.north east) {Problemstellung und Forschungsfragen};
        
        \node[Numbox] (V) at ([yshift=-\numskip]IV.south west) {V.};
        \node[Textbox] (VT) at ([xshift=\textnumskip]V.north east) {Problemstellung und Forschungsfragen};
                
    \end{tikzpicture}   
    
\end{frame}
\end{document}