How to create line from parallel line objects

I have a two tables of lines in SQL Server 2016 database. Each one has a Spatial field with type geometry.
My job is to find lines from table B which are parallel line objects to lines in table A and make line object from them.
The thing is I’m new at spatial SQL and I really can’t figure out how to do that.

My tables look’s like this:

My main line look’s like this, table A:

And example of parallel line objects, table B:

Here is desired result which I’m looking for:

I’ve tried something with ShortestLineTo and delimited lines from table B to start and end points but without any success. Literally any help is welcomed.