Dataset attached to paper titled "Observation of Multi-Directional Energy Transfer in a Hybrid Plasmonic-Excitonic Nanostructure" with time and momentum characterization of a 2D palsmonic heterostructure formed by Au nanoislands on bulk WSe2. It contains Angle-resolved photoemission spectroscopy (ARPES) and time-resolved ARPES data (trARPES.zip); femtosecond electron diffraction (FED) data (FED.zip); optical absorption spectroscopy data (Optical_absorbance.zip) and Transmission electron microscopy micrographs (TEM.zip). For trARPES.zip, the following table reports the grid of measurements and most important parameters: Name Sample temperature (K) Pump Wavelength (nm) Pump Duration (fs) Material trARPES_Metis_002.mpes.nxs 300 800 35 Au/WSe2 trARPES_Phoibos_Scan2124.mpes.nxs 300 800 35 WSe2 trARPES_Phoibos_Scan2146.mpes.nxs 70 800 35 WSe2 trARPES_Phoibos_Scan2197.mpes.nxs* 70 800 35 Au/WSe2 trARPES_Phoibos_Scan2198.mpes.nxs* 70 800 35 Au/WSe2 trARPES_Phoibos_Scan2212.mpes.nxs* 300 800 35 Au/WSe2 trARPES_Phoibos_Scan2219.mpes.nxs* 300 800 35 Au/WSe2 trARPES_Phoibos_Scan3159.mpes.nxs 300 1030 200 Au/WSe2 trARPES_Phoibos_Scan3164.mpes.nxs** 300 1030 200 Au/WSe2 trARPES_Phoibos_Scan3185.mpes.nxs 300 1030 200 WSe2 *These scans are acquired with higher angular dispersion requiring separate scans for K and Sigma valleys. **Fluence scan. FED.zip contains the following subfolders: Manuscript_Figure: Experimental data and fit parameters depicted in Figure 4 of the main article. Analysis: Additional information for the FED data including: raw data descriptions (delay, power, filename and more), Matlab scripts with comments, masks and backgrounds for image processing. The Static_patterns subfolder contains electron diffraction patterns of pure WSe2 flakes and Au-covered WSe2 flakes. Optical_absorbance.zip contains the following subfolders & subfiles: without Au & with Au containing all the optical measurements of pristine and Au-covered WSe2 flakes, respectively. comparison_with_and_without_Au.xlsx contains the analysis of the difference curves manuscript_figure.txt contains the data that were used in Figure 1 of the main article.