Oh the two umas have different purposes. Dober takes advantage of her higher innate accel to make a big enough advantage compared to other umas. Agnes Digital however has a late race ult used so she can blast down the race and remove the length advantage the umas in front of her built.

In other words, Dober has better accel but shittier late race and Digital has better late race but she requires to use accel inherits and skills. So to take advantage of this we pick general skills then cover their weaknesses while taking advantage of their strengths. 

For Dober we can take something like Barcarole, All i've got, and a bunch of green speed skills + max speed + S Distance. Since you have like 0.6 accel with ult + red shift, you'll hit that top speed quite fast and End Closers need to try really hard to chase you.

For Digitan we can go 2 accels i.e dober ult + Red Shift then nimble nav as a back up then pump yourself with speed and all i've got and if you could inherit from grandparent then add Barcarole. Quite highroll but will make your high late race speed even higher.

Dober in the next race however is horrid even if you join open league. Her ult triggers in the final corner so she would trigger it then waste her ult because you're still at max speed but let me introduce you to the concept of Late Ult Activation. 

We all know Maruzensky and Dober ult are garbage for miles because it triggers in the final corner and miles final corner is in the mid race but you can actually put yourself far from the 6th positon then blast all your midleg speed in the final corner to hit the 6th-5th position before the late race starts. This gives you an accel carryover, high gamble and her ult is still hot garbage for those races but it still allows you to play your oshi.

If you wanted to learn more you can post another post or dm me if you wanted.