Did you try Wine? I think it should run on Arch. But not everything is working.

https://appdb.winehq.org/objectManager.php?sClass=version&iId=37735

Microsoft doing it's best that Office won't work on any other OS properly. The best option imo (but also the most painful) is to switch completely to unix based solutions. Regarding energy consumption i think that TeX is very economical (and can be painful too)

The year office 365 is released will be the year of the Linux desktop. Unfortunately I guess that year won't come.

From the research I did a couple years ago, Office 2010 is the newest version that works out-of-the-box on Wine and the later versions have problems related to Windows Update functionality. Codeweaver’s CrossOver seems like it can run Office 2012 and later, but its paid software with their own patches to Wine.

For me, I’ve had a copy of Office 2007 on my system since 2021 and it seems to have all the important features of modern MS Office, so I wouldn’t stress about running the latest version if you have an older version on hand, unless it is older than Office 2007, because those only support the older Office file formats.

Have you tried the online version of Office? 365 I think. I haven't tried it myself, but I've heard that it works well.

As far as Onedrive goes, there's a client that can be set up for real time syncing, like the Windows client. It's also called onedrive, and it's available here:

https://github.com/abraunegg/onedrive

There's a GUI extension by bpozdena that's very good too, and it's linked from the github page 👍

EDIT: Sorry, after I posted I saw where you said you've tried the online version of Office >.<