Most COVID-related rules directly affecting real estate have been rescinded by the state and Federal governments, including the CDC eviction moratorium, which expired on July 31, 2021.
Remember that some municipal governments still have local restrictions on the books - often related to evictions - and some county court systems have instituted special eviction timelines that apply to tenants that have made applications to the Emergency Rental Assistance Program. And of course there are still numerous rules in place covering specific types of interactions (e.g., wearing masks in health care facilities or on planes).
Pennsylvania's business mitigations orders expired on May 31, and the mandatory mask order expired on June 28, 2021.
Businesses, of course, are still permitted to impose additional restrictions if they care to (as is always the case), and it is certainly possible that clients - particularly sellers - may wish to set certain restrictions as part of their business relationship.
These practices are subject to change as the situation continues to evolve and under the guidance of the Pennsylvania Assoc of Realtors, CDC Health Guidelines and the PA Department of Health.