I noticed that Error Corrections began temporarily affecting frames in the area a tiny bit, Project Reality another tiny bit, MMM another tiny bit, Project Beauty a tiny bit. But then, adding FWE and all the associated compatibility files all at once brought that scene to unplayable even with no enemies in the area. The performance drop so far is only temporary where it could drop permanently with all mods activated.
See anything immediately wrong with this current load order?
Spoiler
00 Fallout3.esm [CRC: C092218B]
01 Anchorage.esm [CRC: A4BA9D10]
02 ThePitt.esm [CRC: B38B3E44]
03 StreetLights.esm [CRC: C5690E8E]
04 BrokenSteel.esm [CRC: 30011B79]
05 PointLookout.esm [CRC: D92704D8]
06 Zeta.esm [CRC: 1D017E23]
07 Unofficial Fallout 3 Patch.esm [Version 1.2.0] [CRC: A104CF58]
08 CRAFT.esm [CRC: AE67CA57]
09 CALIBR.esm [Version 1.4] [CRC: 67CE3320]
0A Project Beauty.esm [CRC: 67951301]
0B FO3 Wanderers Edition - Main File.esm [CRC: 9C986068]
0C Mart's Mutant Mod.esm [CRC: 895521AD]
0D Unofficial Fallout 3 Patch - Operation Anchorage.esp [Version 1.2.0] [CRC: CA877E59]
0E Unofficial Fallout 3 Patch - The Pitt.esp [Version 1.2.0] [CRC: 9D96A8DD]
0F Unofficial Fallout 3 Patch - Broken Steel.esp [Version 1.2.0] [CRC: 7B3D59C0]
10 Unofficial Fallout 3 Patch - Point Lookout.esp [Version 1.2.0] [CRC: A9245EB9]
11 Unofficial Fallout 3 Patch - Mothership Zeta.esp [Version 1.2.0] [CRC: 30C44BE5]
** Project Beauty- Broken Steel.esp [CRC: 652432DA]
** Project Beauty- Point Lookout.esp [CRC: 431457E1]
12 FO3 Wanderers Edition - Main File.esp [CRC: 01982EC9]
13 FO3 Wanderers Edition - DLC Anchorage.esp [CRC: D6AA0D05]
14 FO3 Wanderers Edition - DLC The Pitt.esp [CRC: BFF37246]
15 FO3 Wanderers Edition - DLC Broken Steel.esp [CRC: 9226281C]
16 FO3 Wanderers Edition - DLC Point Lookout.esp [CRC: B63AAA64]
17 FO3 Wanderers Edition - DLC Mothership Zeta.esp [CRC: 03CF8025]
18 FO3 Wanderers Edition - Followers Enhanced (BrokenSteel).esp [CRC: 88F5A264]
19 FO3 Wanderers Edition - Optional VATS Halftime.esp [CRC: 1B66E394]
++ FO3 Wanderers Edition - Optional Restore Tracers (automatics only).esp [CRC: E13850C3]
++ FO3 Wanderers Edition - Project Beauty.esp [CRC: D3E4DF34]
++ FO3 Wanderers Edition - Project Beauty (Followers Enhanced).esp [CRC: ADDA0623]
1A Mart's Mutant Mod.esp [CRC: FB3CE701]
1B Mart's Mutant Mod - DLC Anchorage.esp [CRC: 5D392FF2]
1C Mart's Mutant Mod - DLC The Pitt.esp [CRC: 53DC9D8F]
1D Mart's Mutant Mod - DLC Broken Steel.esp [CRC: 89BF5711]
++ Mart's Mutant Mod - DLC Point Lookout.esp [CRC: A4E67116]
1E Mart's Mutant Mod - DLC Zeta.esp [CRC: 627BE465]
** Mart's Mutant Mod - Project Beauty.esp [CRC: DFA6EEA0]
1F Mart's Mutant Mod - FWE Master Release.esp [CRC: 7A8FAA71]
++ Mart's Mutant Mod - FWE Master Release + DLCs.esp [CRC: D6697503]
** Mart's Mutant Mod - FWE Master Release + Project Beauty.esp [CRC: 9B509FB5]
20 F3ProjectRealityMkI.esp [CRC: 78302499]
21 Error Fixes V1.5 - Higher FPS.esp [CRC: E6C3D855]
22 Error Fixes V1.5 - Fallout3 Wanderers Edition.esp [CRC: FDAF4243]
23 Error Fixes V1.5 - Unofficial Fallout 3 Patch.esp [CRC: 6CAEEEA9]
24 Bashed Patch, 0.esp [CRC: D72C6D67]
25 Fallout Remastered.esp [CRC: A71235F6]
26 Fallout Remastered - FWE.esp [CRC: 0B963534]
27 Fallout Remastered - FWE + Project Beauty.esp [CRC: DEC9D2B3]
28 Fallout Remastered - Mart's Mutants Mod.esp [CRC: C79FDE0C]
01 Anchorage.esm [CRC: A4BA9D10]
02 ThePitt.esm [CRC: B38B3E44]
03 StreetLights.esm [CRC: C5690E8E]
04 BrokenSteel.esm [CRC: 30011B79]
05 PointLookout.esm [CRC: D92704D8]
06 Zeta.esm [CRC: 1D017E23]
07 Unofficial Fallout 3 Patch.esm [Version 1.2.0] [CRC: A104CF58]
08 CRAFT.esm [CRC: AE67CA57]
09 CALIBR.esm [Version 1.4] [CRC: 67CE3320]
0A Project Beauty.esm [CRC: 67951301]
0B FO3 Wanderers Edition - Main File.esm [CRC: 9C986068]
0C Mart's Mutant Mod.esm [CRC: 895521AD]
0D Unofficial Fallout 3 Patch - Operation Anchorage.esp [Version 1.2.0] [CRC: CA877E59]
0E Unofficial Fallout 3 Patch - The Pitt.esp [Version 1.2.0] [CRC: 9D96A8DD]
0F Unofficial Fallout 3 Patch - Broken Steel.esp [Version 1.2.0] [CRC: 7B3D59C0]
10 Unofficial Fallout 3 Patch - Point Lookout.esp [Version 1.2.0] [CRC: A9245EB9]
11 Unofficial Fallout 3 Patch - Mothership Zeta.esp [Version 1.2.0] [CRC: 30C44BE5]
** Project Beauty- Broken Steel.esp [CRC: 652432DA]
** Project Beauty- Point Lookout.esp [CRC: 431457E1]
12 FO3 Wanderers Edition - Main File.esp [CRC: 01982EC9]
13 FO3 Wanderers Edition - DLC Anchorage.esp [CRC: D6AA0D05]
14 FO3 Wanderers Edition - DLC The Pitt.esp [CRC: BFF37246]
15 FO3 Wanderers Edition - DLC Broken Steel.esp [CRC: 9226281C]
16 FO3 Wanderers Edition - DLC Point Lookout.esp [CRC: B63AAA64]
17 FO3 Wanderers Edition - DLC Mothership Zeta.esp [CRC: 03CF8025]
18 FO3 Wanderers Edition - Followers Enhanced (BrokenSteel).esp [CRC: 88F5A264]
19 FO3 Wanderers Edition - Optional VATS Halftime.esp [CRC: 1B66E394]
++ FO3 Wanderers Edition - Optional Restore Tracers (automatics only).esp [CRC: E13850C3]
++ FO3 Wanderers Edition - Project Beauty.esp [CRC: D3E4DF34]
++ FO3 Wanderers Edition - Project Beauty (Followers Enhanced).esp [CRC: ADDA0623]
1A Mart's Mutant Mod.esp [CRC: FB3CE701]
1B Mart's Mutant Mod - DLC Anchorage.esp [CRC: 5D392FF2]
1C Mart's Mutant Mod - DLC The Pitt.esp [CRC: 53DC9D8F]
1D Mart's Mutant Mod - DLC Broken Steel.esp [CRC: 89BF5711]
++ Mart's Mutant Mod - DLC Point Lookout.esp [CRC: A4E67116]
1E Mart's Mutant Mod - DLC Zeta.esp [CRC: 627BE465]
** Mart's Mutant Mod - Project Beauty.esp [CRC: DFA6EEA0]
1F Mart's Mutant Mod - FWE Master Release.esp [CRC: 7A8FAA71]
++ Mart's Mutant Mod - FWE Master Release + DLCs.esp [CRC: D6697503]
** Mart's Mutant Mod - FWE Master Release + Project Beauty.esp [CRC: 9B509FB5]
20 F3ProjectRealityMkI.esp [CRC: 78302499]
21 Error Fixes V1.5 - Higher FPS.esp [CRC: E6C3D855]
22 Error Fixes V1.5 - Fallout3 Wanderers Edition.esp [CRC: FDAF4243]
23 Error Fixes V1.5 - Unofficial Fallout 3 Patch.esp [CRC: 6CAEEEA9]
24 Bashed Patch, 0.esp [CRC: D72C6D67]
25 Fallout Remastered.esp [CRC: A71235F6]
26 Fallout Remastered - FWE.esp [CRC: 0B963534]
27 Fallout Remastered - FWE + Project Beauty.esp [CRC: DEC9D2B3]
28 Fallout Remastered - Mart's Mutants Mod.esp [CRC: C79FDE0C]