For some reason, anytime i morph into anything that us not player sized, like a bat or chicken etc, they drift south east non-stop and will get pulled through blocks and cause me to suffocate. Is this fixable or?

As Morph has just been rewritten and released for MC 1.16.5, I am clearing the issue tracker as I have not provided any support Morph for 1.12.2 and earlier. My apologies for not addressing your issue.

Also if anyone's coming across this, This is usually due to a mod conflict, two mods are trying to set the player's size at the same time, every tick

What version of the mod?

Never mind! I believe at the time though it was 1.7. Sorry!

what did you do to fix this?

same issue

how to fix

same issue