Component list that is updated on google drive
Connecting the DRAIN
Shower waste trap like in this video or the picture below. I don't use this product but the look is about right. It could be more shallow so that the shower basin is as low as possible to the floor.
The good thing about this is that it has a thread that you can attach a 1" female to 1/2" male hose connector. Maybe with a 3/4" inch adaptor in between. It's also possible to use PVC pipes with a bigger drain and with space for a dirt lock. Making sure that the screen filter on this drain is very important because it will capture 90% of the largest particles like hair and with a fine mesh skin cells as well. Leaving only tiny things and dissolved solids and liquids to enter the filter.
This one is from Home Depot. I've never been to one of those living in Finland but I like the look of it.