If you have a Cloudflare API token available and are not afraid of a command line, you can turn off the proxy like this:
First grab the zone ID via:
curl -X GET "https://api.cloudflare.com/client/v4/zones" -H "Authorization: Bearer $API_TOKEN" -H "Content-Type: application/json" | jq -r '.result[] | "\(.id) \(.name)"'
And a list of DNS records using:
curl -X GET "https://api.cloudflare.com/client/v4/zones/$ZONE_ID/dns_records" -H "Authorization: Bearer $API_TOKEN" -H "Content-Type: application/json"
Each DNS record will have an ID associated. Finally patch the relevant records:
curl -X PATCH "https://api.cloudflare.com/client/v4/zones/$ZONE_ID/dns_records/$RECORD_ID" -H "Authorization: Bearer $API_TOKEN" -H "Content-Type: application/json" --data '{"proxied":false}'