how to force bigquery to load csv file all column as string without schema and autodetect=False

Question

I have multiple csv files stored in gcs, I want to load them to bigquery using cloud run.

The problem I don't know the schema and the schema is variable always change also I don't want to use autodetect option when load files. I want to load csv files to bigquery using bigquery api loadconfig without schema and autodetect=False, all columns considered of type string.

is that possible ?

I tried to use pandas dataframe , but files are too large so always there is memory problems.