Not sure if this is the right forum but regarding the accessories guide: https://dolphin-emu.org/docs/guides/recommended-accessories-dolphin/
The recommended rechargeable batteries / dock don't work properly with the recommend Motion Plus Controller (they may work with a normal controller though, I don't have any way to check), the rechargeable battery pack is slightly the wrong shape and its impossible to insert the top two tabs and insert the battery pack (I actually broke the metal clip on the bottom of the battery pack trying). It is possible to insert them if you leave the top two tabs out and gently push it in but obviously this has stability problems (and makes it hard to fit into the plastic grip case). You may want to note this in the guide or recommend a separate rechargeable dock for the Motion Plus Controller.
The recommended rechargeable batteries / dock don't work properly with the recommend Motion Plus Controller (they may work with a normal controller though, I don't have any way to check), the rechargeable battery pack is slightly the wrong shape and its impossible to insert the top two tabs and insert the battery pack (I actually broke the metal clip on the bottom of the battery pack trying). It is possible to insert them if you leave the top two tabs out and gently push it in but obviously this has stability problems (and makes it hard to fit into the plastic grip case). You may want to note this in the guide or recommend a separate rechargeable dock for the Motion Plus Controller.