Confused about the whole Ballplayer feature

[jmgarmon_PSN]

So I'm still confused about the whole Ballplayer, RTTS & DD please help me understand.
I've created my player in RTTS , created my player in DD and have created my ball player my questions are:

1. Do the changes I make to my ballplayer carry over into RTTS & DD modes in example Equipment , jersey number etc ?

2. If I do well in RTTS with my Ballplayer will my DD player automatically get better over time without playing him in DD at all?

Thanks

[TheSoloistGamer_XBL]

This guy has the absolute best explanation of Ballplayer. SDS kinda left us hanging.

https://youtu.be/AXS4oTTsr50

[TheSoloistGamer_XBL]

Here's another link that I found as well...
https://www.pushsquare.com/guides/mlb-the-show-21-how-to-upgrade-your-ballplayer-and-unlock-perks

Good luck!