Since v. 2.11.0 of Request a Quote extension, we have added a feature to include simple, virtual, and downloadable out-of-stock products when creating quotes. You can find the ‘amasty/module-request-quote-edit’ package for installing in composer suggest. Please note that the modules are available as a part of an active subscription.
Once the package is installed, a new setting Allow Quote Editing in Statuses would appear in Amasty > Request a quote > Configuration. According to the selected option, it will be possible to edit quotes with a certain status. Once enabled, Edit button would appear for the quotes with the statuses chosen:


The feature is also compatible with Company Account extension, when 'amasty/module-company-quote-edit’ is installed as well. Once done, User roles will gain special permissions if quote editing is enabled in the admin panel. You can grant permission to edit only your own quotes or the quotes of all company members. Additionally, please note that a company's Customer Group will be prioritized over the customer group of company members. If quote placement for certain groups is disabled in the Request a Quote module (ie, if a customer group is not selected in the Allow Quote Request for Customer Groups setting), company members will not be able to place quotes, regardless of their permissions.