No one can know what TPE and Taiwan will be like next March but personally I would be wary of planning a trip based on transit via TPE. Taiwan has more to lose than other countries and is far behind on vaccination relative to other countries so their policy has been extremely conservative. I would seek alternate or at least backup travel plans.

All that said, should TPE and Taiwan fully reopen, traveling into Taipei from TPE is not that difficult with the Taoyuan Airport MRT only taking about 35 minutes to Taipei Main Station where there are many hotel options including Western-brand hotels in the vicinity.