The Ukrainian sports ministry late Wednesday changed its previous policy from barring athletes from facing Russians or Belarusians competing as neutrals.
The new policy says Ukrainians are barred from facing those athletes who "represent the Russian Federation and Belarus".
Smirnova was competing as a neutral.
Four-time world sabre champion Kharlan outclassed Smirnova and fulfilling the promise she made to AFP in an interview a fortnight ago refused to either acknowledge her Russian opponent nor shake her hand at the end of the contest.
The 32-year-old -- who hopes to add the elusive Olympic individual gold next year to complete the full set of titles -- was cheered on by around 20 members of the Ukrainian delegation chanting 'Slava Ukraini' ('Glory to Ukraine').
Smirnova furious at the snub and her loss stood her ground and was still sitting on her chair 10 minutes after the bout.
Kharlan was livid with the IOC and the International Fencing Federation (FIE) for permitting Russians and Belarusians to compete again, albeit as neutral athletes.
Bularus is seen as Russia's ally in the Ukraine invasion.
"How are Ukrainian athletes meant to feel when the IOC should be on our side and delivering justice but in fact they are doing things totally against us?" she told AFP in an interview earlier this month.
Kharlan had, though, expressed her doubts about Ukraine's policy of barring their athletes from events where Russians and Belarusians were competing.
Ukraine's judokas had been pulled out of the world championships earlier this year due to Russians and Belarusians being present.
"It is important to our nation we do not remain on the couch," she said.
"I am really proud of our tennis players and imagining myself in their place, playing or fencing against the people whose country is bombing and killing our compatriots.
"It must be very hard but you know you have to as it is a way of fighting, you are the fighter in your own way."
Ukrainian tennis players have been playing Russians and Belarusians since the invasion in February, 2022, but as individuals not representing their country. They too have avoided shaking hands with their opponents.
"They are right not to shake hands, I cannot imagine a scenario where I would," said Kharlan.
"We have different fronts, we also have sport which is about the fight and the struggle."
