Physical house viewings by estate agents are linked to the Construction Industry under current Covid restrictions. It is anticipated that viewings will recommence when the Construction sector is reopened on 4th March.
But even then, it will likely revert to very limited viewings i.e. you will only be able to book a viewing if you have watched a video of the property online and you have proof of funds. Apparently a lot of estate agents were happy enough with these restrictions in 2020, as it removed the tyre-kickickers and ensured mostly serious viewers attended.
Personally, I think it's fairly risky for a seller to go Sale Agreed based on a virtual viewing. You'd be opening yourself up to the buyer playing the 'oh I didn't realise the house had/hadn't got xyz... I need a discount now' card. You'd have to give them a discount or start over.
2020 was a crazy year for residential property and 2021 is set to be similar. Things will be quiet during L5 lockdowns, and absolute chaos during periods where viewings are permitted.
Particularly in Dublin, the supply shortage has not disappeared and looks set to dictate prices for some time to come, in my opinion