"Standard Partition" scheme is related to partitions themselves, not about the partition table. So, it'll create plain physical partitions, rather than using LVM or BTRFS.
If a partition table already exists on the disk, Fedora will use it since the existing partitions should be preserved.
Fedora will only create a new partition table when there are no partition tables on the disk (so, it is a raw disk without any partitions/partition tables). AFAIK, on these systems Fedora will create a GPT table, even on BIOS systems. GPT is better than MBR anyway. In earlier Fedora versions you were able to force Anaconda to create an MBR rather than GPT by adding a nogpt
(or something similar) option to kernel boot options in initial Fedora installer screen (I don't know how it could be acheived in live versions. Probably you could pass the same option to Anaconda itself). I don't know if such an option still exists.
Finally, AFAIK, in UEFI systems you must use GPT.