This page has a different, simpler approach and more specific steps. Apparently you can just copy the Microsoft EFI folder to a specific directory in your Linux drive’s ESP partition. I’d be a little bit concerned about Windows not being able to update its EFI bootloader, but I also don’t know if Windows ever updates that. The page also has instructions on how to interact with the systemd-boot menu during boot.
You could also install grub yourself, but I can’t guarantee that’ll be easy. Mashing F2 might be the sanest solution, unless you plan on booting into Windows every day.