I have a long quiz with 10 questions in one page. Each have their own validation rules. Is there a convenient way in oTree Lite to place the field error message next to the form field where it happened, other than:

==============================================
    {{ formfield 'my_field1' }}
    {{ formfield_errors 'my_field1' }}
    
    {{ formfield 'my_field2' }}
    {{ formfield_errors 'my_field2' }}
    
    {{ formfield 'my_field3' }}
    {{ formfield_errors 'my_field3' }}
    
    ...
=================================================

The formfield element already includes the errors, so the formfield_errors is redundant here, no? And then that can be reduced to {{ formfields }}.

Yes, but if I use {{ formfields }}, it will display the error message at the top of the block, not right before the question that is wrong. Or am I doing something wrong?

If you want the errors next to the field, you should use FIELD_error_message, not error_message: https://otree.readthedocs.io/en/latest/forms.html#field-name-error-message

Or you can use this technique if you have many fields: https://otree.readthedocs.io/en/latest/misc/tips_and_tricks.html#duplicate-validation-methods