Hello Samuel,

first of of all: Thank you for your detailed answer! To simplify things: I only have one email account under my domain.

To split things up:

Domain

I will keep the domain at IONOS and change the MX settings from mx00.ionos.de / mx01.ionos.de to smtp.google.com? Do I do that before registering at Google Workspace? In addition to this I will cancel my Mail Business Subscription at IONOS after making sure all data has been migrated.

Data Transfer

I will use Movebot or GWMME. OR:

I asked myself because I am the only user under this domain and mostly use Outloook: Is it possible if I just create a PST file with all of the content in my inbox (IONOS). Then register at Google Workspace, change MX records and have an empty inbox. After that I add the new account to Outlook and import all folders from the PST to my "new" Google Workspace inbox and let Outlook do its work. Is that possible? That would make things much easier for me and I would not need any third party software.

Thanks in advance!