Desperate for help. Unknown issue with car

Ive been to several mechanics after trying to fix it
myself. My car broke on my birthday last year. Its
now my birthday again and im about to give up
after a year of tinkering.

Okay this is long but im just gonna start from the
beginning

I have a show car thats all done up. Its a 2000
celica gt automatic with a 2zz ge engine swap. Car
was fast as hell i could top out my spedometer.
Had a full body kit and lambo doors. My engine
blew and i had no choice but to try and drive it
home. I found out i blew a rod bearing and ground
it and my crank to the point of no return. So i did
an engine swap myself on my front lawn over
christmas holidays (im in canada... thats how
much i wanted this car back) well engine swap
went fine. When i first started it i heard a nasty
grinding sound i thought was coming from the bell
housing. So i shut it off imediately and towed it to
a mechanic to make sure i didnt mess anything
up. Turns out the grinding was just my power
steering pump amd the sound was just echoing
throung the bell housing on the top. So i towed the
car back home and replaced the pump and wires. I
start it up again. Runs rough for awhile then levels
out. Idles mint. It never idled well before the engine
blew. In park and neatral it used to rev up to 4000
and down. Up and down. Uo and down every few
seconds but as soon as you put it in drive it ran
right.

Well this is now were im at. It idles fine. Car wont
accelerate at all. Its like its not shifting.the car
wont go above 40km an hour. Thats with it floored.
Itll also be redlined. I can trick it into shifting by
getting it up to 40 and then letting go of the gas
and stomping it a few times but the revs are
always really high and itll lag. Like it will rev way
up but nothing for a second then ill get a kick and
then levels out again or it will be julty.

I did have an engine light come on. Malfunctioning
rev sensor and a knock sensor code. I replaced the
rev sensor because that seemed like the obvious
reason to me. Still nothing. An entire mechanic
shop has been looking at it for a few months and
they gave up. Now its sitting inbhind their shop in
a grass feild because i dont know what to do with
it. Ive given the mechanics over a grand just to tell
me if its my tranny thats gone aswell or if it some
stupid little issue. They gave up. Im down to
replacing the knock sensor and that prolly wont
work so then im down to parting out the car ive
rebuilt 3 times. And spents thousands on and its
still has no rust and looks brand new.

Please help me out. Ive checked fluids. I cant get a
good reading the the ATF level but ive put the
exact amount that i took out when i did the swap. I
also added extra. Then took out the extra and then
some. Didnt make a difference