You need to perform an inner join and ignore spaces in the values.
In Power Query, to handle joins where values may contain spaces or minor mismatches, you use fuzzy matching in the Merge Queries operation.
Append queries combines rows, not columns, so it does not apply here.
Lookup table is not required since the transformation can be handled natively in Power Query with fuzzy matching.
Correct solution: Merge the queries by using fuzzy matching.
Reference: Fuzzy merge in Power Query