There are fraud problems with mail-in absentee ballots but the problems with universal mail-in ballots are much more significant. Still most countries ban even absentee ballots for people living in their countries.

Most developed countries ban absentee ballots unless the citizen is living abroad or require Photo-IDs to obtain those ballots. Even higher percentages of European Union or other European countries ban absentee for in country voters. In addition, some countries that allow voting by mail for citizens living the country don’t allow it for everyone. For example, Japan and Poland have limited mail-in voting to those who have special certificates verifying that they are disabled.

France has made an exception in 2020 to the ban absentee ballots to those who are sick or at particular risk during the Coronavirus pandemic. Poland and two cities in Russia have adopted mail-in ballots for elections this year only, but most countries haven't changed their regulations.