When looking at east and west sides, some crossed models were left over from the fix. Here is the list;
Cobweb
Calibrated Sculk Sensor
Crimson & Warped fungus
All Amethyst stages
Flowering/Azalea
Kelp
Tall/Seagrass
Twisted Vines
Weeping Vines
Hangings Roots
All Corals
Small Dripleaf
Big Dripleaf
The flame of campfires and soul campfires
Mangrove propagule planted on the ground
Potted mangrove propagule
Potted saplings, potted fern, potted dead bush, potted crimson/warped roots, all potted flowers, potted red/brown mushrooms, potted Nether fungi
Mangrove propagule hanging from leaves
Nether sprouts
Sugar cane
Pitcher crop (partially, the new model is z-fighting with the old one
Crop-shaped models (wheat crops, beetroots. carrots, potatoes, nether wart) have already been reported in MCPE-146936, which should be marked as related.
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Seagrass, crops and nether wart should be moved to a separate ticket due to them having a different model (not cross-shaped).
In addition to the blocks listed in the report, the bug also still affects the following blocks when viewed from west or east:
Potted saplings, potted fern, potted dead bush, potted crimson/warped roots, all potted flowers, potted red/brown mushrooms, potted Nether fungi
Mangrove propagule hanging from leaves
Nether sprouts
Sugar cane
Pumpkin and melon stems (they are mirrored in Java as well, but it's inconsistent with all the other cross models and not their original intended appearance)
Pitcher crop (partially, the new model is z-fighting with the old one, should be reported separately)
And the following blocks when viewed from north or south
The flame of campfires and soul campfires
Mangrove propagule planted on the ground
Potted mangrove propagule
Feel free to add these to your report

I don't agree for Kelp because it is using a crossed models.

Nether warts are in fact cross-shaped too. They are a cluster of cross-shaped models that form part of the same block. The same concept applies to seagrass and crops.

Crop-shaped models (wheat crops, beetroots. carrots, potatoes, nether wart) have already been reported in MCPE-146936, which should be marked as related.

Can confirm 1.21.60.23.

1.21.70.20 has fixed many of these. The only remaining issues are:
Mangrove propagule
Hanging mangrove propagule
Potted mangrove propagule
Wall- and ceiling-mounted amethyst buds/crystals
Calibrated sculk sensor (amethyst crystal)
Campfire (flame)
Soul campfire (flame)
Big dripleaf (stem)
Small dripleaf (stem)
Pumpkin stem (this is also an issue in Java)
Melon stem (also in Java)
Seagrass
Tall seagrass
The following seem to be partially fixed, but the old model is z-fighting with the new one:
Kelp top
Nether sprouts
Crimson fungus
Warped fungus
Potted flowers
Potted saplings
Potted mushrooms
Potted fern
Potted dead bush
Potted azaleas (inner planes)
Potted nether fungi
Potted nether roots

All Amethyst stages stuck to the walls and ceiling has not been fixed yet.

@boda kugga It seems all of the blocks that are now z-fighting only do it on certain coordinates, and on some coordinates they look normal without the z-fighting

After inserting the resource pack, the mooshroom mushroom model is still incomplete.

I can confirm the comment from "boda kugga". 1.21.70.20 silently fixed most of the issues from this report, in addition to stretching most cross models (see MCPE-188479) so the ADO should be updated to reflect the current issue.
Also, amethyst cluster and buds are still not double-sided when placed on walls or ceilings.
[media]Even the Mooshroom model was updated!
[media]

Mooshrooms are not completely fixed yet. Put in various resource packs and look at the mushrooms.

Replying to vindi546
I'm not sure what the issue is. Here is the Plastic texture pack with the new Mooshroom model. The mushrooms are still stretched and double-sided, and they match the current texture pack.
The mushrooms float above the back of the mooshroom, but that is not related to the double-sided or stretched part of the model. That's a positioning issue!
[media]

Pay attention to the stem of the mushroom.

Replying to vindi546:
Good find. That should probably be a separate bug report since it's technically an entity model, not a block model.

Since the blocks affected by this issue change almost every preview, updating this report is not the right way to keep track of the most recent issues. Instead, there are now separate reports for all the remaining issues:
Potted flowers: MCPE-190486
Calibrated Sculk Sensor amethyst: MCPE-190469
Wall and ceiling Amethyst Cluster/Buds: MCPE-190421
Sweet Berry Bush: MCPE-190470
Mangrove Propagule: MCPE-190468
Campfire flame: MCPE-190471
Small Dripleaf stem: MCPE-122375
Big Dripleaf stem: MCPE-122372
Kelp top: MCPE-190473
Crimson and Warped Fungus Z-fighting: MCPE-190389
Mooshroom back mushroom Z-fighting: MCPE-190291
To see a related list of stretching issues, see the comments of MCPE-188479.
It would make the most sense to close this report as "Fixed in 1.21.70.22", as the remaining issues will be handled separately.

1.21.70.22 has reverted all changes listed in pinned comment that were made in 1.21.70.20, so now in latest beta blocks like pot is not double-sided and it's displayed wrongly from east and west sides.

Replying to Mega611:
I can confirm what you are saying for the flower pot:
[media]
However, the other fixes like Amethyst are still in the game:
[media]
The flower pot issue is now reported as MCPE-190486.

This report should be marked “Fixed in 1.21.70” as the vast majority of cross model issues have been resolved. The remaining issues have been splintered into separate bug reports for each blockshape.
These cross models should be double-sided, but currently aren't:
Potted Flowers: MCPE-190486
Mooshroom Back Mushrooms: MCPE-190811
Mangrove Propagules: MCPE-190468
Campfires: MCPE-190471
Calibrated Sculk Sensor: MCPE-190469
Wall/Ceiling Amethyst Clusters/Buds: MCPE-190421
Big Dripleaf: MCPE-122372
Small Dripleaf: MCPE-122375
Sweet Berry Bush: MCPE-190470
These cross models should be stretched, but currently aren't:
Calibrated Sculk Sensor: MCPE-169777
Sweet Berry Bush: MCPE-190470