Teams list update via excel

Hi MauritsElias 

Thanks for raising your question! See article

https://support.office.com/en-us/article/collaborate-on-files-in-microsoft-teams-9b200289-dbac-4823-85bd-628a5c7bb0ae

As the article states, 

Files stored in your team's file library are accessible to every member of the Team. In Office for the web, Office for Android or iOS, or the latest applications from Office 365, you and your team members can co-edit Word, PowerPoint, or Excel documents, or comment on Visio files

You can open or edit the document

1.) In Teams
2.) In Excel (the desktop version)
3.) In Excel (the online version in the browser)

If you want to replace a file with the same name, simply go to the file tab of the Team and upload the document with the same name, it will ask you to replace it

Note, SharePoint underlies the Teams file experience so it should not be too difficult to do what you need

Hope that answers your question

Best, Chris