You can do this through singleValueExtendedProperties.
There is more on how to create these here https://learn.microsoft.com/en-us/graph/api/singlevaluelegacyextendedproperty-post-singlevalueextendedproperties?view=graph-rest-1.0
Depending on your language you are using you'll have to tweak it based on the prop.id of "Binary {00062008-0000-0000-C000-000000000046} Id 0x00008520".
There is a stackoverflow answer using the JavaSDK here https://stackoverflow.com/questions/68667907/send-exchange-email-with-voting-buttons-using-ms-exchange-graph-api-java-sdk/68668010#68668010
Code copied here for archival
// send an email
Message message = new Message();
message.subject = "Meet for lunch?";
ItemBody body = new ItemBody();
body.contentType = BodyType.TEXT;
body.content = "The new cafeteria is open.";
message.body = body;
EmailAddress emailAddress = new EmailAddress();
emailAddress.address = to;
Recipient toRecipient = new Recipient();
toRecipient.emailAddress = emailAddress;
message.toRecipients = List.of(toRecipient);
EmailAddress fromAddress = new EmailAddress();
fromAddress.address = sendingMailbox;
Recipient fromRecipient = new Recipient();
fromRecipient.emailAddress = fromAddress;
message.from = fromRecipient;
VotingButtonEncoder vbe = new VotingButtonEncoderImpl();
SingleValueLegacyExtendedProperty prop =
new SingleValueLegacyExtendedProperty();
prop.value = vbe.createVoteButtonsBase64String(
List.of("Yes, let's have lunch.", "No, thank you though."));
// https://learn.microsoft.com/en-us/openspecs/exchange_server_protocols/ms-oxprops/e11cc753-cecf-4fdc-bec7-23304d12388a
prop.id = "Binary {00062008-0000-0000-C000-000000000046} Id 0x00008520";
List<com.microsoft.graph.options.Option> requestOptions =
new ArrayList<>();
String requestUrl = "https://graph.microsoft.com/v1.0/users/"
+ sendingMailbox + "/microsoft.graph.sendMail";
SingleValueLegacyExtendedPropertyCollectionRequestBuilder builder =
new SingleValueLegacyExtendedPropertyCollectionRequestBuilder(
requestUrl, graphClient, requestOptions);
List<SingleValueLegacyExtendedProperty> pageContents =
new ArrayList<>();
pageContents.add(prop);
SingleValueLegacyExtendedPropertyCollectionPage singleValueExtPropPage =
new SingleValueLegacyExtendedPropertyCollectionPage(
pageContents, builder);
message.singleValueExtendedProperties = singleValueExtPropPage;
boolean saveToSentItems = true;
graphClient.users(sendingMailbox)
.sendMail(UserSendMailParameterSet.newBuilder()
.withMessage(message)
.withSaveToSentItems(saveToSentItems).build())
.buildRequest().post();