Errata » Professor's Research | Trainers » Professor's Research
In the Expanded format, there's already a rule that says you can't include Professor Sycamore and Professor Juniper in the same deck; players must choose one or the other. The same rule applies to Professor's Research, meaning it cannot be in the same deck as Professor Sycamore or Professor Juniper.
Source: TPCi Announcement (2020-01-09), TPCi Rules Team (2020-01-09)

Relevant cards

Note: All applicable cards may not be listed below.
SWSH1_178
SWSH1_178
SWSH1_201
SWSH1_201
SWSH1_209
SWSH1_209
BW1_101
BW10_84
BW5_98
BW9_116
XY1_122