Dear Mirko,
Good day! Thank you for posting your query in our community.
Per your description, when you import via Excel Legacy Wizard From Web, values that begin with zero are formatted as numbers.
Based on my research, currently, it is not available now. Because when you import from the wizard, there is no option for you to select the cell type.
A workaround I can think of is that you could change the type of the cell manually after importing.
Thanks for understanding.
Sincerely,
Jazlyn | Microsoft Community Moderator
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