I have a 2004 Honda Civic Hybrid, and the transmission went out today.

Issues: It had a shudder when accelerating from 0-10 MPH but went away after topping off transmission fluid, but came back a few weeks later(trans fluid still read full)
Transmission Fluid is clean(no metal shavings, red, not burnt)
No issue precluding the transmission just stopping...

I was at a stop sign, started driving(car shuddered like it always does) then about 4 seconds later the engine revved way up.
I thought I accidentally bumped it into neutral, but saw I was still in drive. Will not engage in reverse, drive, or the S or L...

No noises, no slipping transmission.. any ideas before I swap it out? I keep seeing about the TRS, but cant find the link on how to check it...

Also, as a noteworthy statement, when in Drive and Reverse, I can push it both directions, but it locks in Park. So when in reverse I can push forward, and reverse and it will roll....

Also, earlier in the driveway, I had it in reverse, and it was CRRREEEEEEEPPPIIIINNNGGG, like an inch a minute, when in reverse....

Thank you everyone who has the time to give their input