Please write review to this thread, if you find good (or not so good) accessories for Leste devices.

I found small carry bag for Pinephone Keyboard (Pinephone wiith Pinephone Keyboard option):
Fjällräven High Coast Pocket F23226 (code is important to get carry stripe, there is another without it)

It has two pockets, bigger pocket is like designed for Pinephone Keyboard, smaller pocket is like designed for charging cable and small charger (like Deltaco DBS15Q) or surprisingly another Leste devices (N900 or Droid4) fits in.

It has disconnectable long carry stripe or you can use with your belt to carry on.

Bad point is that it is very expensive compared to size.

Battery charger for Pinephone from Pine:
https://pine64.com/product/pinephone-battery-charger/

This charger is important. If you get battery total empty (in normal use it is not possible, device shut off before that comes) with this you can start charging.

There is many power banks available for Leste devices, but I noticed that Hayden Power Bank 20 work with all Leste devices (tested N900, Droid4, Pinephone, Pinephone Keyboard), you can even charge it to half capacity with original Nokia N900 charger and then quick charge (PD) Pinephone Keyboard (it has enough capacity (full is 20000mAh) to both batterys 3000mAh + 6000 mAh) with it, remember put it to keyboard side of USB-connector not phone side connector.

It is also about same size than two Pinephones (Hayden 163x83x21mm and Pinephone 160,5x76.6x9.2mm)