Overlap between values in a row in one dataframe and colums in other dataframe : This should be straightforward, but I am kind of stuck.

Dataframe (df1) has column with chr variable, some of these values in that column correspond to column names in other data frame (df2).
I would need to find an overlap between values (rows) of that column in df1 and all the columns in df2.
Since the number of these columns is > ~1200, I can not filter one by one.

Is there another elegant way other than transpose?

Thank you in advance.

