Covid-19 vaccines are used for prevention of viral disease. If incidentally if any person got infected to coronavirus after vaccination then had vaccination has any affect on transmission of disease to others.
Vaccines generally do not prevent all infection. If you look hard enough you may find that a vaccinated individual can get infected. However, a good vaccine will prevent disease. Typically one would expect that a vaccinated individual will not shed as much virus as an unvaccinated person, but that will need to be examined. The killed polio vaccine is an example of a vaccine that does not prevent the intial infection in the gut, but does inhibit a secondary virema which serves to prevent paralytic polio. The Covid-19 vaccine produces a decent IgG response, some IgA. My guess is that it will severely limit spread of virus coming from vaccinated individuals, but if you look hard enough you will still find some virus shedding.
Since scientists haven't yet found evidence that the vaccines provide mucosal immunity, someone who is vaccinated and has no symptoms of illness may be carrying the live SARS-CoV-2 virus and spreading it to others when they cough, breath or sneeze. https://www.smithsonianmag.com/science-nature/yes-you-should-still-wear-mask-after-covid-19-vaccination-180977054/