How long will it take to get use to the fanned frets?
Frets 1 through 12, the adjustment is primarily visual. Don’t look at your fretting hand and you will be amazed at how natural the fanned-frets feel. 10 minutes is a common adjustment period for positions in these frets.
Above the 12th fret, there is a bit more of an adjustment, but the benefits in clarity outweigh any adjustment efforts. Chords above the 12th fret require the most adjustment. Although some voicings will be easier, some may require a change of fingering. The upside is the potential for new and interesting voicings and the ability to increase your “stretch” due to the angle of the frets. It is truly an adventure.