Karpova: This game was played in the 1st Class tournament (<Turnier 1. Klasse>) of the St. Petersburg Chess Society.
On 7.Ng3, the annotator mentions Znosko-Borovsky vs S F Lebedev, 1903 for an interesting, but incorrect sacrifice (15.Nxf7).
Instead of 12...Nf6, Black had the interesting option 12...Bxf3 13.Qxf3 (13.gxf3 Qg5) 13...Ne5.
16...Rhf8, the annotator mentions <16...Bxd3 17.Qxd3 c5>.
21...e5 looks like an interesting possibility.
25...fxe5 doesn't appear best, maybe <25...Rxd4 26.Rxb8+> Kxb8 27.Rb3+ Rb4 28.axb4 fxe5 and Black may put up some resistance.
26.exd5 was possibly stronger.
27...c4 was not annotated, but looks weak. Perhaps 27...cxd4, to make c5 available to the ♕.
Source: 'Wiener Schachzeitung', July-August 1906, pp. 252-253