On 28 January 2021 The Finnish embassy in Hanoi announced:
The municipal elections are approaching! Do you have a home county in Finland, but are you temporarily staying abroad during the municipal elections? Order letter voting material from the Ministry of Justice’s order service starting on 18.1.2021:You should order the materials without delay, because the current exceptional circumstances can affect the passage of mail and early voting abroad itself.
Read the comprehensive article by Finland-Seura ry about the municipal elections here