Type conversion while querying from DB

I don't know if you could try to cast the result of the query as a similar CDT with the same fields but sometimes a different datatype for a given field, and that could be within the same rule as the QE.  You could save the .data of the query result into a rule input whose type is a similar CDT.  It won't work with a local variable because they take on the type of whatever you put in them.  It's possible that implicit casting would take over.  If it works, this is probably the simplest approach outside of synched records, which you should definitely check out if you can.

Aside from that, no, you get the data as step one, and then convert it as needed as step two.

I don't know if you could try to cast the result of the query as a similar CDT with the same fields but sometimes a different datatype for a given field, and that could be within the same rule as the QE.  You could save the .data of the query result into a rule input whose type is a similar CDT.  It won't work with a local variable because they take on the type of whatever you put in them.  It's possible that implicit casting would take over.  If it works, this is probably the simplest approach outside of synched records, which you should definitely check out if you can.

Aside from that, no, you get the data as step one, and then convert it as needed as step two.