I bring up converting this set due to the DVD CHDs made with the new mode seeming to run better and be a bit smaller on average than ones made via the previous way, converting them would make it easier for anyone in the future who wants to use this collection since they won't have to re-convert it if they own lower-end hardware or are low on storage/don't have much in the first place. If it's not possible due to a lack of storage space or time, I can download all the files in the PS2 section and do the conversion myself and host it on so that you can download it and add it to the collection here.
The command for this, batch or otherwise is the same as the one for CDs, just take the Cue to CHD command and change (*.cue) to (*.iso) and createcd to createdvd. I have checked by converting my own iso files and one from here by extracting and re compressing and can confirm that these CHDs work with PCSX2 already, Due to this I believe that you should probably update the current DVD PS2 games in this set with ones made with that mode.
Mame added the option to make DVD CHDs in their update May 31st update, the PS2 section seems to mostly have CHDs made before then so it's all either made with the CD command or with the RAW command.