There is no direct way.
If you add the two shows in a regular fashion, and if the episodes have a suitable “Originally Aired” date, you can use this workaround: Watch crossover episodes of several series in-order
There is no direct way.
If you add the two shows in a regular fashion, and if the episodes have a suitable “Originally Aired” date, you can use this workaround: Watch crossover episodes of several series in-order