Cleaning The Drain Hose ??
I would not brother, It will clean itself once you start using the machine properly,
Worrying about the inside of the drain hose is like taking your house apart to clean the drainage lines.
We see dirty washers like this all the time, when we get them in the shop they will clean themselves but it might take 20-40 loads with heavy detergent and some LCB but they do come clean without disassembly.
We had a full sized Miele FL washer come in the shop about a year ago, it was the dirtiest washer I had ever seen reeked to high heaven, after about 30 loads the machine looked like new when we had to take it apart for a spider replacement.
John