Well, the way you've been framing the issue suggests that you expect international reactions to range from indifference to outright approval. I submit that even if those are the initial impressions, once the implications of this move set in, there would be more disapproval, and the Russians would be considered the aggressors in hindsight. This in turn will make Britain and France less tolerant of future assertive moves than they would have been IOTL, with all the potential for conflagration that entails.
France was going to start active participation in Piedmont's wars against Austria. There was no love lost between 2nd Republic and Austrian Empire and if Nicholas was a little bit more accommodating, he would manage to get along with Nappy #3 as well (the issue about the Holy Sites could be resolved to everyone's satisfaction).
Unhappiness of the Brits would be practically guaranteed no matter what Russia was doing so it could be safely ignored. What happens in an unidentified future is anybody's guess.