Field in schemata below relationships but in JSONapi below attributes which results in schema mismatch

Problem/Motivation

We have a field "field_article_seo" which is a Metatag field within a node entity. The jsonapi?_format=json lists the field below relationships (see screenshot), on the resource for the node entity the field is below attributes which causes a schemata mismatch in an external application relying on this.

The following versions of modules are used:

• Entity API: 8.x-1.5
• JSON:API Extras: 8.x-3.26
• JSON:API Resources: 8.x-1.2
• Metatag: 2.0.0
• OpenAPI: 8.x-2.2
• OpenAPI for JSON:API: 3.0.5
• OpenAPI UI: 1.0-rc5
• Schemata: 1.0.0

Any ideas on this how to get this fixed?