drain hose for chest freezer
A siphon might be better if it is a lot of water.
1:  No hose will fit in.  That drain hole has a flat side.  I wondered what sort of plug thing would go it.  The answer looks like &quot;none&quot;.  The instruction manual https://c.searspartsdirect.com/mmh/lis_pdf/OWNM/L0702364.pdf
says that water should just drip out into a pan.  Another source recommended a bunch of towels.
2:  You will need to reach through all the water to unplug the drain.  Doable but not fun.  I hope you have long, orangutan like arms for this endeavor, and in general.

Siphon.  I think you might be better off siphoning the bulk of the water out.  You can siphon it out with a garden hose to the drain.  You wont have to get wet or use all your towels.  I change the water in my aquarium this way.  If you want every last bit you can get that with the drain hole and the pan.

Are walls strong enough for this use?  I worry that if this freezer is really full of water and ice it will produce a lot of lateral pressure on the walls.  I do not think the walls of a freezer are made to withstand that kind of pressure.  Make sure the environment of this freezer will be safe if a wall comes loose while you are out of town.