Does 7.0.1 require hibernate6?

No, support for hibernate 6 is not done yet. But work is being done to support it in the future, possibly on Grails 7.1.x

I see, Thanks @sbglasius, Reason why I am asking this because I changed one of my projects from 7.0.0 to 7.0.1 it gives out this error:

Caused by: java.lang.NoSuchMethodError: 'org.hibernate.cfg.AccessType org.hibernate.cfg.AccessType.getAccessStrategy(jakarta.persistence.AccessType)'
	at org.grails.orm.hibernate.cfg.GrailsDomainBinder.bindProperty(GrailsDomainBinder.java:2699)
Caused by: java.lang.NoSuchMethodError: 'org.hibernate.cfg.AccessType org.hibernate.cfg.AccessType.getAccessStrategy(jakarta.persistence.AccessType)'

	at org.grails.orm.hibernate.cfg.GrailsDomainBinder.bindSimpleId(GrailsDomainBinder.java:2658)
	at org.grails.orm.hibernate.cfg.GrailsDomainBinder.bindIdentity(GrailsDomainBinder.java:1874)
	at org.grails.orm.hibernate.cfg.GrailsDomainBinder.bindRootPersistentClassCommonValues(GrailsDomainBinder.java:1825)
	at org.grails.orm.hibernate.cfg.GrailsDomainBinder.bindRoot(GrailsDomainBinder.java:1451)
	at org.grails.orm.hibernate.cfg.GrailsDomainBinder.contribute(GrailsDomainBinder.java:216)
	at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.complete(MetadataBuildingProcess.java:292)
	at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.build(MetadataBuildingProcess.java:86)
	at org.hibernate.boot.internal.MetadataBuilderImpl.build(MetadataBuilderImpl.java:479)
	at org.hibernate.boot.internal.MetadataBuilderImpl.build(MetadataBuilderImpl.java:85)
	at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:709)
	at org.grails.orm.hibernate.cfg.HibernateMappingContextConfiguration.buildSessionFactory(HibernateMappingContextConfiguration.java:319)
	at org.grails.orm.hibernate.connections.HibernateConnectionSourceFactory.create(HibernateConnectionSourceFactory.java:109)
	at org.grails.orm.hibernate.connections.AbstractHibernateConnectionSourceFactory.create(AbstractHibernateConnectionSourceFactory.java:63)
	at org.grails.orm.hibernate.connections.AbstractHibernateConnectionSourceFactory.create(AbstractHibernateConnectionSourceFactory.java:47)
	at org.grails.datastore.mapping.core.connections.AbstractConnectionSourceFactory.create(AbstractConnectionSourceFactory.java:83)
	at org.grails.datastore.mapping.core.connections.AbstractConnectionSourceFactory.create(AbstractConnectionSourceFactory.java:71)
	at org.grails.datastore.mapping.core.connections.ConnectionSourcesInitializer.create(ConnectionSourcesInitializer.groovy:45)
	at org.grails.orm.hibernate.HibernateDatastore.<init>(HibernateDatastore.java:228)
	at java.base/jdk.internal.reflect.DirectConstructorHandleAccessor.newInstance(DirectConstructorHandleAccessor.java:62)
	at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:499)
	at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:483)
	at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:210)
	... 118 common frames omitted

looks like a hibernate version issue

Do you still have a specific hibernate version i your dependencies? Compare with a vanilla Grails 7.0.1 app.

no, I did not. I used the one comes with the grails default. but I have hibernate-ehcache specified with 5.6.15.Final.

implementation "org.apache.grails:grails-data-hibernate5"
    implementation("org.apache.grails:grails-data-hibernate5-dbmigration") {
        exclude group: 'org.slf4j'
    }
    implementation "org.hibernate:hibernate-ehcache:5.6.15.Final"

This my dependencies file

sorry, did not realize can not attach a file

but from dependencies I could not find hibernate6 either, I guess this is something else

After I followed the document to put exclude in, the exception is gone. Thanks for replying

implementation "org.hibernate:hibernate-ehcache:5.6.15.Final", {
    exclude group: 'org.hibernate', module: 'hibernate-core'
}