I find this super unfortunate since the dp eq settings are specifically crafted for their internal speakers, and will always sound bad in an external sound system, which probably will have its own equalizer anyway.
Agree there should be a "direct" option, but there may be times you want to record the equalized sound. Perhaps another set of "direct" outputs, or a software or hardware switch?
I don't think you'd ever want to use the EQs for recording, at least not the ones in the ES110. For this piano there's 3 options: "normal", "table" and "off". "Normal" is designed for a stand, with increased highs and decreased mid frequencies. "Table" is for when you use the piano on a table, it has decreased bass to compensate for the table's reflection of bass frequencies. Off is just off.
Both "normal" and "table" sound awful on external speakers since they're taylored for this particular piano's speakers and cabinet, but they actually work amazingly well for the internal sound. In fact, when EQ is off the internal speakers sound like a muddy mess (hence particularily bad for monitoring), barely usable at all.
I think this is just a mistake from the manufacturer. Don't see any scenario where anybody would want to use these ugly EQ presets for line outs, while they're superb for the piano's speakers.