Can't get past this database incompatibility. Need help

Your software v4.3.1
My PHP version is : 7.4
My MySQL/MariaDB version is (delete as applicable): MySQL/MariaDB version v8.0

Updating/Installing Errors
I am: Updating
Upgrading/installing via : Command Line

These errors are showing in the installer :
An exception occurred while executing ‘ALTER TABLE oauth2_accesstokens ADD CONSTRAINT FK_XXXXXXXXXXXXXXXX FOREIGN KEY (user_id) REFERENCES users (id) ON DELETE CASCADE’:
SQLSTATE[HY000]: General error: 3780 Referencing column ‘user_id’ and referenced column ‘id’ in foreign key constraint ‘FK_XXXXXXXXXXXXXXXX’ are incompatible.

These errors are showing in the Mautic log :

Your problem
My problem is : I can’t sort this (and I assume other) foreign key constraint issues. Schema update fails, won’t complete.

Steps I have tried to fix the problem :
I have tried all these tips: and these: and even manually addressing the constraints in the DB without success.

I gave up. Installed a fresh 4.3.1 and now have to manually migrate all my data. Fun.