The /entity/entity_form_display/{entity_form_display} should works.
Example:
/entity/entity_form_display/node.article.default?_format=json
It will return json like this:
{
"uuid": "058dd73d-366d-466d-9393-ad0d5d44e928",
"langcode": "en",
"status": true,
"dependencies": {
"config": [
"field.field.node.article.body",
"field.field.node.article.comment",
"field.field.node.article.field_image",
"field.field.node.article.field_location",
"field.field.node.article.field_tags",
"image.style.thumbnail",
"node.type.article"
],
"module": [
"comment",
"image",
"path",
"text"
]
},
"id": "node.article.default",
"targetEntityType": "node",
"bundle": "article",
"mode": "default",
"content": {
"body": {
"type": "text_textarea_with_summary",
"weight": 1,
"region": "content",
"settings": {
"rows": 9,
"summary_rows": 3,
"placeholder": ""
},
"third_party_settings": []
},
"comment": {
"type": "comment_default",
"weight": 20,
"region": "content",
"settings": [],
"third_party_settings": []
},
"created": {
"type": "datetime_timestamp",
"weight": 10,
"region": "content",
"settings": [],
"third_party_settings": []
},
"field_image": {
"type": "image_image",
"weight": 4,
"region": "content",
"settings": {
"progress_indicator": "throbber",
"preview_image_style": "thumbnail"
},
"third_party_settings": []
},
"field_location": {
"weight": 121,
"settings": [],
"third_party_settings": [],
"type": "options_select",
"region": "content"
},
"field_tags": {
"type": "entity_reference_autocomplete_tags",
"weight": 3,
"region": "content",
"settings": {
"match_operator": "CONTAINS",
"size": 60,
"placeholder": ""
},
"third_party_settings": []
},
"path": {
"type": "path",
"weight": 30,
"region": "content",
"settings": [],
"third_party_settings": []
},
"promote": {
"type": "boolean_checkbox",
"settings": {
"display_label": true
},
"weight": 15,
"region": "content",
"third_party_settings": []
},
"status": {
"type": "boolean_checkbox",
"settings": {
"display_label": true
},
"weight": 120,
"region": "content",
"third_party_settings": []
},
"sticky": {
"type": "boolean_checkbox",
"settings": {
"display_label": true
},
"weight": 16,
"region": "content",
"third_party_settings": []
},
"title": {
"type": "string_textfield",
"weight": 0,
"region": "content",
"settings": {
"size": 60,
"placeholder": ""
},
"third_party_settings": []
},
"uid": {
"type": "entity_reference_autocomplete",
"weight": 5,
"region": "content",
"settings": {
"match_operator": "CONTAINS",
"size": 60,
"placeholder": ""
},
"third_party_settings": []
}
},
"hidden": []
}