As said by Patt22, if you want RIGHT NOW 8 variations styles (and a ton of other advanced features, more on this later) you have a choice:
https://www.groovyband.live/xg/. It works on ALL Yamaha arrangers and digital pianos (based on XG standard), no matter how old they are. A reasonable level could be Tyros3/PSR770 or newer. It is available since 2018. There is a demo with 906 styles you can download and use for free, forever.
Let us see some advanced features it offers, you can only dream off on Yamaha HW:
1 ) Styles with 8 variations/fills (including half bar fills), 2 breaks, 3 intros/endings. A variation can be easily customised in real time with the style playing at the push of a button. For each of the 8 parts just select one pattern (there are 4 to choose from) or mute it. You have therefore 4^8 > 65k combinations possible. When you find a combination that you like store it in one of the 8 slots available. Se also point 7).
2 ) 8x2 OTSes (each of the 8 OTS has 2 programmable variations). You decide the association between OTS and variation, possibly with the same OTS linked to many variations. You can rearrange the order of variations/OTSes as you like, maintaining the correct links between them.
3 ) Full and free use of all available DSPs (you decide on what of the 16 parts to use them), including stacking 2 of them for each part. For example with a Genos you can use 16 DSPs, in 16x1 or 8x2 configurations. You can easily edit them (tweak all parameters) and save presets.
4 ) Four lead parts, that can be partitioned between right/left hand as you like, for every OTS. For example you can have an OTS with 1L/3R, another with 4R, another with 2L/2R, and so on.
5 ) Programmable harmonization function for EACH lead part (you have 4 independent harmonizers).
6 ) You can manage up to 4 midi devices, including 3 keyboards/pedalboards. You have 8 tracks for style parts, 4 tracks for lead parts (L/R hands, under OTS control), and for 4 "aux" parts to assign to the additional keyboard(s)/pedalboard. You can create split/layers at will with the aux parts. The aux parts configuration is programmable for each style.
7) You can customise any voice, effect or other parameter for any style variation. For example let us say you have a track with a guitar riff. You could set for variation A a clean solid guitar. On variation B you add more chorus. On variation C you tweak the sustain. On variation D you change the voice to a rock guitar with distortion. On variation E you tweak the distortion effect, ......
8 ) The program uses vector graphics and scales with razor sharp images to any resolution/screen size. Touch screens are supported. You can also assign every command to physical controls (buttons/knobs/keys/wheels, ...) of attached midi devices.
9 ) A lot more, .... check the online manual (
https://www.groovyband.live/xg/manual/)
10 ) By the way, you can control slow/fast rotary effect with a button/wheel and pedal wah with a pedal/wheel.
We also have a version that works on Yamaha MODX/Montage synths, transforming them in state of the art arrangers:
https://www.groovyband.live/modx/.