I dunno how to swap it through Cheat engine as I really don't know how to use it properly but if you were to do it through swapping the enemies files, it would work for ya.
Use this thread to learn how to extract the RE2 Remake .pak file :
How to extract .pak and Use NoesisTo find all the files for the enemies, just use this here :
RE2 - Ultimate File ListTyrant would be em6200 whereas G1 Birkin would be em7000.
Just make a folder, call it whatever and add these folders to it : (Your Folder's name)\natives\x64\objectroot\prefab\character\enemy
Just copy the em7000 file you got from following the .pak thread into the enemy folder and rename it to "em6200.pfb.16" instead.
You'll then need Fluffy's Mod Manager which you can read about in this thread :
Modding PAK files
If you follow that all correctly and place the folder you named into the RE2R Mods folder in the mod manager, it all should work.
I may have just made this harder for myself or I dunno because this is my first time trying this as I only found out how to do it all today.
Hope you get it working if you do attempt this and I also hope you have fun with it.