"MILANO GUARD BGT FLAG" Topic

Desperately seeking information about Milano Guard Battalion 1813 Flag.

thank for helping

I assume you mean "battaglione della Guardia della città di Milano".
Looking at Art. 2 of the formative decree of 10 Decemeber 1811, there is no provision for a battalion standard-bearer among its staff.

I can't find anything specific for what they carried in 1813, likely some sort of fanion, not national colors.
Perhaps the new coat of arm for the city granted on 9 Janaury 1813 would provide a good basis for a conjectural fanion?
« Porta lo scudo d'argento colla croce piana e centrata di rosso; terminato dal capo di verde colla lettera N d'oro posta nel cuore ed accostata da tre rose a sei foglie del medesimo; Cimato dalla corona murale a sette merli, d'oro, sormontata dall'aquila nascente al naturale, tenente tra gli artigli un caduceo d'oro in fascia. Il tutto accompagnato da due festoni intrecciati d'ulivo e di quercia dell'ultimo, divisi tra i due fianchi, ricongiunti e pendenti dalla punta »

As far as I know, the compagnies de réserve departementale in France did not receive any orders with regard to flags or fanions. The battaglione della Guardia della città di Milano was a formation of a generally similar type.

I will be very interested in any other colleague's greater knowledge.

Hoping to be helpful, no mention of flags.
napitalia.org.uk/eng/milgd.shtml

Consider that even the Veliti della Guardia did not received flags at the start, having it only after the 1812 campaign, so this unit with a not so high status is doubtful receive it at all.