Power Query Merge Columns if Not Null

I have a data model that I would like to merge only the columns (6 total) that don't have null values. For example, one row might have 5 names in the 6 columns so I would only want to combine the first 5 names and not the 6th null value. The next row might have only 3 names so I only need the first 3 names and not the 4th 5th and 6th null values.

I was also hoping it might be possible that after I combine the names that I could somehow place them in alphabetical order. eg. Change - Dave, Bob, Adam to Adam, Dave, Bob.

Thanks