Here's something that may help.
n = 3;
data = rand(10,n);
f = figure();
tl = tiledlayout(2,n);
d = gobjects(n,1);
for ii = 1:n
nexttile(tl)
d(ii) = donutchart(data(:,ii));
end
tl = tiledlayout(tl,1,1);
tl.Layout.Tile = n+1;
tl.Layout.TileSpan = [1,n];
ax = nexttile(tl);
ax.Visible = 'off';
c = d(1).ColorOrder;
nc = size(c,1);
nd = numel(d(1).Data);
c = repmat(c,ceil(nd/nc),1);
p = cellfun(@(x)patch(ax,NaN,NaN,x),num2cell(c(1:nd,:),2));
set(p,'FaceAlpha',d(1).FaceAlpha);
d(1).LabelsMode = 'manual';
d(1).Names = "slice "+(1:nd);
legend(p,d(1).Names,'Orientation','horizontal','NumColumns',ceil(nd/2));
