When making selections in Time-Series (Line-Charts) with the rectangular lasso, interactions with other Line-Charts can only be set to "Filter" or "Off" but not to "Highlight".
As a result, a selected region (by lasso) from Figure A only shows the filtered data in Figure B, loosing the overall context within Figure B.
To maintain the context from Figure B, it would be very helpful if the interaction could be set to "highlight".
This functionality is already intrinsically implemented: Line charts with legend-grouping can be highlighted when clicking on a single/multiple legend-groups (see below: only "LAS|R" selected/highlighted)
See another example from a statistical software which has this functionality:
The screenshot plots the same y-data over different (production-)timestamps.
The data is interactively filtered by a "rectangular lasso" within the third-row-figure (see dashed rectangle).
As a result, the corresponding points in all the other figures are highlighted, too.
(In addition, you can move around the rectangle and the highlighted data adapts instantaneously)
Line charts with lines-only could be highlighted with the help of an indicator variable which is set as legend, allowing to compare "selected"-group vs. "non-selected"-group lines.