I got it to work (correct me if this might cause problems)
1- Install Dolphin 5.0 Stable then run it and close it once
2- go to %USERPROFILE%\Documents\Dolphin Emulator\Wii\shared2\
3- copy all folders except the folder named "sys" to anywhere safe like the desktop
4- delete the "Dolphin Emulator" folder from %USERPROFILE%\Documents\
5- run the new dolphin version then close it
6- move the previously copied folders to the newly created %USERPROFILE%\Documents\Dolphin Emulator\Wii\shared2\
*now your DLCs will work normally in the new version of Dolphin.
7- Run Dolphin --> Tools --> install WAD --> (choose the DLC)
now when you run the game it will have the DLC
This also works for the Dolphin core in RetroArch:
1- Do steps 1-7
2- Copy the same folders from step 3 to: {RetroArch Directory}\saves\dolphin-emu\User\Wii\shared2\
3- copy the folders "ticket" and "title" from: %USERPROFILE%\Documents\Dolphin Emulator\Wii\ to: {RetroArch Directory}\saves\dolphin-emu\User\Wii\
4- Run the game in RetroArch and play the game normally
1- Install Dolphin 5.0 Stable then run it and close it once
2- go to %USERPROFILE%\Documents\Dolphin Emulator\Wii\shared2\
3- copy all folders except the folder named "sys" to anywhere safe like the desktop
4- delete the "Dolphin Emulator" folder from %USERPROFILE%\Documents\
5- run the new dolphin version then close it
6- move the previously copied folders to the newly created %USERPROFILE%\Documents\Dolphin Emulator\Wii\shared2\
*now your DLCs will work normally in the new version of Dolphin.
7- Run Dolphin --> Tools --> install WAD --> (choose the DLC)
now when you run the game it will have the DLC
This also works for the Dolphin core in RetroArch:
1- Do steps 1-7
2- Copy the same folders from step 3 to: {RetroArch Directory}\saves\dolphin-emu\User\Wii\shared2\
3- copy the folders "ticket" and "title" from: %USERPROFILE%\Documents\Dolphin Emulator\Wii\ to: {RetroArch Directory}\saves\dolphin-emu\User\Wii\
4- Run the game in RetroArch and play the game normally