I currently only use tutanota and proton for my email but... If you have a bunch of accounts I suggest MailStore Home (free from Germany).
http://www.mailstore.com/en/mailstore-home-email-archiving.aspx
Gmail or Yahoo! Mail
Any POP3 and IMAP mailboxes
Microsoft Outlook 2003, 2007, 2010, 2013, 2016
Windows Mail und Windows Live Mail
Microsoft Exchange Server 2003, 2007, 2010, 2013 and 2016 mailboxes
Microsoft Office 365 (Exchange Online)
Mozilla Thunderbird and SeaMonkey
PST, EML and other files
Can be run portable and designed so you can archive locally. Highly recommended.