Can't say definitely because some vendors do re-register their e-charts to WGS-84 and some do not. You have to contact the e-chart vendor to find out. Raster charts are scanned images
of actual paper charts so you can look in the margin/corner and read what the datum is. Some chart management programs can read the "headers" on the e-charts and tell you what is the datum in use for that chart. Most e-nav programs have somewhere in their system a menu items to call up the chart information which would include the datum in use.
- - But in every case you do not bet your boat on the e-chart or even a paper chart being accurate especially if it is linked to an active GPS and has a "little boat" symbol displaying where it thinks you are located. You must confirm visually or by radar
whether you really are there.