[APP] Motion Blinds have tubular motors to integrate in 25mm tubes of just about any roller blind, feature bi-directional communication (locally but requiring a small usb hub), are rechargeable and supported in Homey (shameless plug by the app developer 
) They proved very reliable to me.
They are in stock at RobbSmarrt in the Netherlands: ROBB Smarrt Motion accumotor 433Mhz voor rolgordijn - ROBBshop and they ship internationally.
The Motion products are also sold internationally by other vendors, but I do not know if they are sold in Denmark. They sell their parts to other manufacturers so they just might be sold under different brand names, but they all rely on the Motion Blinds app and have quite recognizable remotes. I recently spoke to some one who might know resellers, so I’ll ask around.
