We are starting to provide support for Mac's but the issue we are running into is that none of our support staff uses Mac so when an issue is brought to them they are not sure what to do.
I've looked at Apple's website and came across http://training.apple.com/pdf/macOS_Support_Essentials_10.12_Course_Description_Sierra_101.pdf. Looking at what the course covers it looks very basic and I'm not sure it would add much value for the cost. I'd be wanting something that digs more into issues that may be encountered in an Enterprise environment such Active Directory topics, troubleshooting Wireless networking such as 802.1x, logon issues, security topics, and basically how to support an end user in this type of environment.
We would be looking for options located in Europe and Asia and preferably would like on-site (traveling to the training center would be an option) however if that's not possible then remote training could be an option as well.
In addition to classroom training, I've found nothing beats actual day-to-day immersion into the Mac world. Setup a Mac with multiple displays and let them use a VM and/or Microsoft Remote Desktop so they can still make RDP connections to do their Windows support tasks. MacOS on one screen and Windows on the other. The success of any training will depend on how much animosity your support staff has against the Mac.
Definitely what @AVmcclint suggested - there's no substitute for having your support staff regularly use a Mac. I'm in a K12 school district with over 80 sites, and manage one of only two sites that is "allowed" to have Macs. When issues are escalated to the district level techs we get much better support from the ones that have Macs for daily use.
I personally would recommend two courses...one is the Support Essentials class, the other is to combine that with Jamf's CCT class.
the Apple Support Essentials class gets you the fundamentals of macOS and is offered by Apple training centers.
The Jamf CCT class will get you going on the Enterprise support side at a technician level. Jamf does offer courses in Hong Kong, London, Stuttgart, Paris and Amsterdam if that helps. I will say that Jamf's instructors are top-notch, and three of my technicians have now passed their CCT, coming away with useful knowledge. I actually am willing to delegate some tasks that I didn't used to as a result. https://www.jamf.com/training/certified-casper-technician-cct/
I also second having the support staff use a Mac. You can't support something you don't use regularly at least at a proper level.
If you're on a limited budget, another option is the Mac videos on lynda.com They have a good one that explains the differences between Windows 10 and MacOS. I've found that has helped our Windows-only techs who have never seen a Mac before understand the basics of what's different. There are some videos that are very rudimentary - the kind you'd make your grandmother watch before you give her her first computer, but you can sift through them.
I've found that the Apple Support training courses assume you are already a Mac user and you just need to be taken to the next level. Those courses are a waste on people who don't know how to turn a Mac on.