never seen that done.

I don't think there is a "mainstream" requirement, although there may be some fringe military/nuclear stuff.

In most cases, baking it prior to use can ruin it.  Many wire lubricants added by the manuyfacturer can flash off at temps as low as 250F....not to mention that you can run into trouble with a masonite spool, cardboard liner or even coated metal carrier.

When in doubt, and in the absence of customer/regulatory requirements, ask the manufacturer for information.

The only time that I have seen mention of baking the FCAW electrodes was written in FEMA 353 Paragraph 3.3.3 Electrode Storage and Exposure Limits.
The way I read it and interpetted it was if the original mfg's plastic wrapping had been damaged then you could redry per the mfg's recommendaations. Also if welding is to be suspended for more than 8 hrs, the wire is to be taken off the machine and stored in an oven and maintained between 250F - 550F or as recommended by the mfg. Spools had to be identified and exposure needed to be documented and any wire exceeding an accumulated exposure time of 24 could not be used in Seismic Weld Demand Category A or B.