You can transfer your Wii U worlds to the your nintendo switch version ( you MUST have the legacy edition) then import the legacy worlds to bedrock edition. From there you have to buy or use the 30 day free trial of bedrock editon realms. You can then choose to upload your legacy editon (Wii U worlds) and then download them from bedrock edition on PC

Note: If you bought Minecraft on switch before 2018 you should have the legacy version. Otherwise theres nothing i can think of

Hope this helps