More settings for crossfading - duration, easing algorithm, etc.

[Crystalwarrior]

Is your feature request related to a problem? Please describe.
it sucks not being able to tweak crossfade duration, so that would be beneficial to be able to tweak it to something that feels comfortable to you specifically. DRO 1.6.0 crossfading actually allows you to do so as well - though it caps out at 600ms, I think we can cap ours at a ridiculous amount for whatever reason lol

also: easing algorithms, this one is even more fine-tuned control but it would led you tweak the CURVES:
https://doc.qt.io/qt-6/qeasingcurve.html

Describe the solution you'd like
settings option for duration
settings option that's a dropdown for easing algorithm