I've already changed the brake fluid on both my '14 DL1000 and '18 DL1000, few times.
First, to change fluid, if you know how to do it, it's straight forward. The only difference is that you'll have to bleed it few times after change as some bubbles will be there. I guess it's because of ABS pump. Not a big deal. 2-3 times, after 2-300 miles of using the bike.
As for the rear, on both bikes I simply removed the screw for rear reservoir. No other screw needed as the reservoir stayed upwards so it was easy to add fresh fluid. After the change was done, put the cover on and screw it back into it's bracket. As easy as that.
I always do it with the bike on side stand.