It looks like you're trying to create a stackedplot with 2 lines per axes which is demonstrated here:
Instead of grouping columns of data in cell arrays, you just need to group the variable names together. It appears you want the lines to be grouped as [Var2, Var1], [Var4, Var3], [Var6, Var5], etc. Here's how to achieve that with stackedplot.
D = array2table(rand(10,8)); % demo table
varPairs = [D.Properties.VariableNames(2:2:end)', ...
D.Properties.VariableNames(1:2:end)'];
pairedVars = arrayfun(@(r){varPairs{r,:}},1:size(varPairs,1),'UniformOutput',false)'; %#ok<CCAT1>
stackedplot(D,pairedVars)
