Lots of the route are footpaths and get really busy at the weekend, you’ll most likely have a verbal clash at some point along it.
Here’s a alternative that uses legal trails and uses Offa’s Dyke sections that are legal to ride and to be honest is a fair bit more rideable than some of the cheeky sections if you stuck the path all the way along it.
http://www.theedgecycleworks.com/mtbroutes/north-wales-coast-2-coast-day-4/
It starts a Gweryd Lakes but that’s only a few miles down the back lanes from Llandegla village anyway.
On MBNW we have had an annual ride of the route over the past few years in June/July with some minor tweaks as its a good long day out, and after we ride home for another 30km when we get to Prestatyn, so a good test of the legs, 100% rideable when it’s dry but expect a ton of hard climbing.